Friday, September 23, 2016

Maude Lina West Cleghorn: A little-known amateur entomologist

I recently came across the works of Miss Maude Lina West Cleghorn and was surprised by the breadth of her entomology research conducted in Calcutta. Miss Cleghorn actively studied insect pollination as an amateur and apparently some government-supported studies on the genetics of voltinism in silkworm in the early 1900s and remarkably little is known of her despite her being a Fellow of the (Royal) Entomological Society, the Linnean Society and the Zoological Society of London. Enquiries with the Linnean Society reveal that she was elected Fellow on the 4th of December 1913, nominated by Isaac Henry Burkill (director of the Botanic Gardens at Singapore); David Hooper (economic botanist with the Botanical Survey of India) and Lawrence Lewton-Brain (director of agriculture, Federated Malay States). Her address was given as 57, Ballygunge Circular Road, Calcutta and a bit before that period at 12, Alipore Road. All that can be found is that she died in 1946 - a single line mention of her death (as Associate Member - a class created in 1835 which according to the byelaws- "Associate Members shall be persons well known for their literary or scientific attainments, but who are not likely to apply to become Ordinary Members.") is found in the Journal of the Asiatic Society of Bengal for 1949.

Among Miss Cleghorn's studies is one on the longevity of insects, specifically silkworm. She notes in passing that a  Hypolimnas bolina lived for 92 days but she examines the lengths to which the moths live based on the season in which the pupae eclose. The graphs are very elegant summaries of her findings (Edward Tufte would admire the simple lines rather than broad bars).

Miss Cleghorn notes that adults emerging in the rainy season are short-lived

She also studied insect-pollination in some detail and especially interesting is her description of trap pollination in two species of Araceae. The first study was in 1913 on Colocasia (Kachu) and she described how cross pollination was enforced by a combination of protogyny by the flower and the timing with which the flower trapped and released carrion flies. She followed up this with a study the next year on Typhonium trilobatum (and she uses the local name Ghet-Khechu!), a member of the Araceae which has a spadix that releases a strong smell of rotting carrion in the evening and keeps the beetles overnight inside the cavity formed by the spathe. It attracts beetles including those in the Coprinae (Scarabaeidae) - and two species are identified Onthophagus tarandus and Caccobius dimiunitivus - the voucher specimens from these flowers were deposited in the Pusa collection and these life-history notes are included with some care in the Fauna of British India (Arrow, Gilbert John (1931) The Fauna of British India. Coleoptera Lammelicornia. Part III (Coprinae). London: Taylor and Francis. pp. 143-144, 181-182.)
Trap mechanism in Typhonium for beetles.

Burkill, the nominator of Cleghorn for Fellow of the Linnean Society, has a very interesting review of pollination mechanisms in Indian plants and he seconds Cleghorn's observations.

Observations of flowers on the trees with field-glasses and close ups of some flowers.
Fig. 1.—Rough sketch made from bunch actually growing on the tree, and observe 1 through field-glasses, showing young buds as seen on the morning of the 14th March.
Fig. 2.—Rough sketch of the same bunch on the morning of the 16th March, which shows the buds taking up the drooping position but with no styles projecting.
Fig. 3.—Sketch of the same bunch in Figs. I and 2, drawn on the morning of the 19th March. Tt shows the buds more pendant, and in two or three of the buds the styles appeared to be protruding slightly as far as could be made out with the glasses.
Fig 4.—Rough sketch of two bunches on the tree with buds older than those shown in Figs. 1, 2, and 3. Sketched on the morning of the 12th March. Three buds on the right bunch had styles protruding. On the left bunch one of the flowers was beginning to " ripen."  On the 13th March two more flowers on the left bunch were becoming fleshy.
Fig. 5.—The same two bunches as shown in Fig. 4, but sketched on the 14th March. The left bunch had four flowers with ripe corollas while the right bunch had two. On the loth March only one ripe flower was left on the right bunch. On the 19th March two of the younger buds of the bunch on the right had become fleshy and had styles protruding.
Fig. 6.—Sketch of two buds on a flowering branch as they appeared on the 2nd April.
Fig. 7.—The same buds sketched on the 5th April. But B which was of the same age as A when cut on the 2nd April was shedding pollen on the evening of the 5th April. The corolla at this stage is almost completely covered by the sepals.
Fig. 8.—Bud-like flower in  first  stage   sketched   on   the evening of   the 5th April.    When lightly tapped, pollen was shed  through the pore-like openings and when the style was touched through the tip of the corolla tube.
Fig. 8a.—Slightly enlarged drawing of flower in the first stage with the tip of one of the sepals turned back to show the opening through which the pollen is shed. There were two other openings just under the tip of the opposite sepals but they were not so large.

Fig. 9 —Section of flower in the first stage. At this stage the anthers are ripe and the stigma sticky and when tapped or shaken at night it produces a shower of pollen. Sketched at 2 a.m. on the 29th March.
Fig. 10.—Section of flower in second stage with much enlarged fleshy corolla, and pollen shed.    Natural size.
Fig. 11.—Sketch of fully "ripe" flower with the much enlarged and fleshy corolla. In this stage the style is about half an inch longer than it was in the first stage. Natural size.
Figs. 12-17 give sketches of a bud and flowers of different ages. The flowering branch was cut at 6-30 p.m. on the 9th April and the flowers were examined almost immediately after.
[In taking the exact measurement of the lengths of the sepals, corollas and styles the sections became slightly distorted and wider.    The exact lengths are shown in the drawings.]
Fig. 12.—Sepals much  longer than petals, style only little longer than the sepals.    Anthers immature and no pollen shed when tapped.
Fig. 13.—Pollen being shed and fleshy part of corolla still completely hidden under sepals.
Fig. 14.—Pollen being shed. Style and petal slightly longer than that of flower shown in Fig. 13.
Fig. 15.—Fleshy part slightly thicker than that in Fig. 13. Appears to be a bit older than that in Fig. 13.
Fig. 16.—Section of old flower in which corolla has fallen off. The style was much longer than the old style of that in Fig- 15, but the sepals were of the same length.
Fig. 17.—Section of old flower showing corolla shed and ovary slightly larger. Sepals the same length as that in Fig. 15, but style found to be exactly 1 cm longer.
Figs. 18-31 give the sections of all the flowers found on a bunch which was examined about 8 a.m. Altogether there were fourteen flowers and none were destroyed by bats.
Fig. 18.—Quite a young bud.
Fig. 19.—Flower in first stage shedding pollen.
Fig. 21.—Most of the pollen shed.
Fig. 26.—Pollen shed thickly.
Figs. 29.-31.—Old flowers which have lost their fleshy corollas.
Fig. 32 shows two stamens enlarged about twice the natural size.

She seems to have maintained an interest in floral biology and pollination for long and her last publication appears to be in 1922 when she wrote on the floral biology of the Mahua (Madhuca longifolia) and noted that it is quite unique and how contemporary botany texts missed out its details. She notes that contrary to some illustrations, the Mahua flower never opens up. She notes that (emphasis mine) - "the mechanism found ... in which a large portion of the actual flower is edible is a rather costly and uncertain one...and appears to be rare among plants. The only other plant with this type of mechanism, recorded so far, is Fracinclea, a pandanus-like plant of Java, which is pollinated by bats while visiting the flowers for the edible bracts." She observed flowers using field-glasses and drew diagrams to demonstrate how the pollen were dispersed through a pore on the side of the otherwise closed bud-like or berry-like flower. The pollen collects inside the closed corolla cup of the hanging flowers in the initial stage and bats going to feed on them get the underside of their wings dusted with pollen. As the flower matures the anthers wither and the corolla becomes fleshy and the stigma becomes receptive. Once the corolla is eaten the stigma is exposed and the bats deposit pollen on them. This aging mechanism ensures cross-pollination.

It seems likely from the names listed in the pages of the Journal that some of Miss Cleghorn's relatives attended the monthly meetings of the Asiatic Society of Bengal. Cleghorn also took an interest in other taxa, there is a mention of her maintaining a live Kaloula pulchra. Harold Maxwell-Lefroy (Imperial Entomologist) in 1916 notes that Miss Cleghorn was to be offered the work on cross-breeding silkworm. It appears that from 1910, "it was decided to prepare a scheme to employ Miss Cleghorn". A visit to Pusa is noted. It seems that she worked on cross-breeding European silkworm which produced high quality silk and produced just one generation a year (univoltine) and Indian varieties that produced multiple generations in a year (multi/polyvoltine) but coarser silk. Cleghorn conducted a series of breeding experiments to examine the heritability of multivoltinism and her conclusion was that multivoltinism was a dominant trait in females but recessive in males.

There is a mention of a Mr J(ames?). Cleghorn, an executive engineer at Cuttack who curiously was engaged in sericulture research. According to a Memorandum by a certain Liotard : "In Cuttack, sericulture has been carried out as an experiment since 1877 at Government expense, under the supervision of the Executive Engineer of the Mahanadi Division." and there is a comment by Mukerji, N.G. in his 1903 A monograph on the silk fabrics of Bengal-:
The reference here is no doubt to the experiments of Mr. J. Cleghorn of the Public Works Department. Mr. Cleghorn's experiments were not altogether fruitless. He published his studies of the life-history of the parasitic fly, and brought to light the great destruction caused by it. He produced some valuable races of beautifully white cocoons, both annual and poly vol tine. He also claimed to have discovered a simple means of avoiding or destroying the fly-pest. But as he could not be induced to part with his secret for less than a lakh of rupees, nothing is known with regard to his method of coping with one of the chief enemies of sericulture in Bengal. The fine races of cocoons he was rearing in conjunction with the Secretary of the Agri-Horticultural Society were not given out to the world either, and Mr. Cleghorn's researches and experiments have, therefore, left little of practical value behind. 
The fly mentioned here is of course Exorista bombycis (Tachinidae) and I wonder if this might be Miss Cleghorn's father, perhaps a clever but money-minded man.

Hopefully someone in a better position to research her life will do justice to this very observant and insightful amateur entomologist whose contributions to pollination biology are almost unknown. I bumped into this remarkable and little-known researcher while looking up on Hugh Cleghorn - one of the pioneers of forestry in India- on whom a most comprehensive biography has just been published by Henry Noltie.


Thanks are due to Lynda Brooks at the Linnean Society for tracking down some details and to Ann Sylph at the Zoological Society of London for checking their archives.


1 comment:

  1. A most remarkable amateur entomologist. Thanks for bringing out such unsung heroes (in gender neutral sense, please!). The Madhuca story is very interesting, even now it is worth pursuing flowering biology and pollination aspects in some detail. Bats apart, the fleshy flowers filled with nectar are also a favourite of sloth bears! In MP, present day Chattisgarh and Jharkhand one sure way of spotting sloth bears is to sit out on a Madhuca tree in flowering season. There is also sufficient scope for man-animal conflict because the local people enjoy their drink made by fermenting the flower nectar which can be quite copious!