TRANSACTIONS OP THE SECTIONS. Ill 



positor ; the appendages of the upper arch and the sternites, together constitute the 

 active part of the organ, and are lodged in the fissure left between the episternites. 



The facility for examination and interpretation of the nature of the parts are very 

 considerable in Machilis ; the existence of the abdominal limbs, so obvious in that 

 genus, enables us to see the true relations of the other parts. The ovipositor consists 

 of four slender, flexible, and slightly club-shaped filaments, closely united to each 

 other by means of interlocking hairs and teeih ; the two outermost are evidently the 

 sternites of the eighth urite ; they are of greater diameter and length than the two 

 others, to which they form a sort of sheath ; the latter are the sternites of the ninth 

 urite, and differ but slightly from the other two. This view of the nature of the 

 organ does not imply that unnatural transference in position of parts which follows 

 from adopting the other theory. 



On the application {for oeconomic and sanitary objects) of the principle of 

 " Vivaria" to Agriculture and other purposes of life. By James 

 Fulton. 

 This paper consisted of suggestions in carrying out on a most extended field the 



application of glass to cultivation, on the above principle. 



On the Coregoni of Scotland. By Sir William Jardine, Bart., 

 F.R.S.E. 



These fish form a considerable group, and in geographical distribution range chiefly 

 over Northern Europe and North America, but are found also in Central Europe and 

 in Great Britain and Ireland. In structure they have been generally placed with the 

 salmon ; but they are by no means typical, and differ in their large scales, the form 

 of their mouth and minute teeth, and in their habits being more gregarious, as they 

 are generally found in large shoals. In all these points they are related to the 

 herring. In Scotland, the localities yet known as inhabited by the Coregoni, are the 

 lochs at Lochmaben in Dumfries-shire, Loch Lomond and Loch Eke in Dumbarton- 

 shire, though from the description of fish taken in other lochs, there can be no 

 doubt that their range is more extensive, and reaches further northward. Those of 

 Lochraaben are undoubtedh' distinct from those of Loch Lomond, but until lately 

 those of Loch Eke were regarded as identical with the latter. The author then 

 pointed out the differences between the three Scotch species, C. Willuyhhii, C. clu- 

 peoides and C. lavaretus, and exhibited specimens to the Section. 



On transparent Fishes from Messina. By Professor Kolliker, Wurzbury. 

 Professor Kolliker exhibited specimens and made some remarks on the structure 

 of some transparent and otherwise peculiar fishes, recently obtained by him from 

 Messina, viz. Leptocephalus vitreus and Helmichthys diaphanus. These fishes, 

 when alive and in water, are so transparent as scarcely to be perceptible. Iq their 

 external form they are allied to the eels, but they possess a skeleton which is only ia 

 the embryonic state. 



On the Development of Sex in Social Insects. 

 By the Rev. William Leitch, A.M., Monimail Manse. 



The author commenced his researches with the view of ascertaining the circum- 

 stances that determine the development of the grub of the neuter bee into a queen. 

 In the course of his observations, a much wider physiological question presented 

 itself, viz. the determination of sex in general in the case of insects in which the 

 triple distinction of sex is found to exist. He has not, as yet, satisfactorily verified 

 his results in any social insects except the hive bee, his observations on which 

 extend over many years. The hives he employed were a combination of the leaf 

 hive and the thin single-comb hive, the one being readily converted into the other 

 while the colony is in active operation. The single-comb hive was so constructed 

 that any small portion of the comb could be readily removed, and eggs and brood 

 transferred from one cell to another. A speculum was employed, by which, with- 

 out removing the comb from the hive, the eggs and grubs, at the bottom of the cells. 



