426 SECTIONAL TRANSACTIONS.—D. 
condition known as microsporidiosis or Nosema disease; May sickness, a tem- 
porary malady of bee colonies, claimed by Turesson to be caused by moulds in 
pollen or honey; and Acarine disease, resulting from the invasion of the 
tracheal system by the mite Z'arsonemus woodi, n.sp. ‘lhe overwhelming 
majority of cases of adult bee disease in this country are cases of Acarine 
disease. T'arsonemus woodi, a member of the family Tarsonemide, is a hetero- 
stigmatic mite, only the females possessing a tracheate respiratory system. It 
invades the anterior thoracic tracheal system, breeding and feeding in this 
situation. Only adults, the males rarely, are found outside the bee. Inflam- 
matory reactions result in the chitinisation of the tracheal wall, the oxygen 
supply is vitiated and restricted, and there is evidence of muscular degeneration. 
The disease is chronic; bees may live a long time even after they are unable 
to fly, but they cease to share in the co-operative work of the colony. The 
course of the disease within a colony varies according to the size of the colony, 
the age and fertility of the queen, the type of original infection, whether 
multiple or not, and possibly the breed of the bee. 
23. Prof. J. F. Gemmitu.—On the Bionomics of the Wheat-bulb 
Disease Fly, Lepto-hylemyia coarctata, Fall. 
The larva causes widespread damage to young wheat. In Scotland there is 
only one generation in each year. The eggs are laid on bare soil, preferably 
on potato fields between the plants, in autumn. The larve, which hatch out 
in early spring, pupate in early summer, and the flies emerge towards the end 
of June. Newly hatched larve seek out and bore into young wheat plants near 
the bulb, destroying the inner tissue, and migrating when necessary to other 
shoots. Couch-grass, rye, barley, and a garden ribbon grass are highly sus- 
ceptible and can nourish the larve from emergence up to normal pupation. 
Larvee taken from any of them can complete their growth in wheat, and vice 
versa. Oats and many field and sand grasses are immune. In nature, couch- 
grass appears to serve as the main ‘reservoir’ for the insect, apart from wheat. 
The influence on the eggs and larve of cold, moisture, depth of ploughing, and 
various manures and disinfectants, is outlined. Remedial measures should aim 
at prevention and the courses to be adopted follow from the life-history. 
24, Major F. W. Craaca, M.D.—Observations on the Organ of Berlese 
in Cimex and on the Behaviour of the Spermatozoa. 
The author drew attention to the special features of the reproductive system 
of the female Cimex hemiptera, Fabricius, pointing out that the sperms pass 
into an asymmetrical organ (organ of Berlese) through minute pores (organ of 
Ribaga). Later they pass through its walls into the body cavity, then into the 
epermathece, and into the walls of the oviduct, up which they pass to the 
follicular epithelium, penetrating it to fertilise the eggs. The development of 
the embryo begins while the egg is in the ovariole. A number of sections 
demonstrating these appearances were shown. 
25. Dr. Nevson ANNANDALE.—Convergence in Shell-sculpture in the 
Viviparide. 
The Viviparide, a family of Gastropod Molluscs of ancient origin and of 
wide range in all geographical regions except the Neotropical, have, as a rule, 
smooth shells. At certain places and at certain geological periods the shells 
of at any rate a large proportion of the species have become sculptured in a 
peculiar manner. The most conspicuous instances are the late tertiary Vivi- 
paride of Slavonia, those of the Greek Archipelago, the living and sub-fossil 
Margaryc of the lakes of Yunnan, and the living and sub-fossil 7aie@ of the 
Inlé basin in the Southern Shan States. The differences in shell-structure 
between the various series were discussed and the anatomical basis for the 
sculpture described. 
26. Major W. S. Parron.—The Diptera which cause Myiasis in Man 
and Animals in India. 
Recently, with the help of a grant from the Indian Research Fund Associa- 
tion, an appeal was issued to all medical and veterinary officers in India, Assam, 
and Burma for living Dipterous larve from cases of myiasis. By breeding out 
