574 



the oval and the fusiform. The latter are the more numerous, and 

 are the rod-like nuclei of Kolliker. Two or even three of these may 

 be observed in the length of a single fibre. If a single muscular 

 fibre of the bladder is isolated, it will be found to terminate as in 

 voluntary muscle ; connective tissue investing not only the fibre, but 

 each of the separate portions into which it ultimately divides. 



The author considers that the 'sarcous elements' of voluntary 

 muscle are represented by the lines of dots visible in the muscular 

 fibres of the bladder. 



II. " On the Ova and Pseudova of Insects." By JOHN LUB- 

 BOCK, Esq., F.R.S., F.L.S., F.G.S. Received Nov. 10, 



1858. 



(Abstract.) 



In the 'Philosophical Transactions' for 1857, I endeavoured to 

 show that the agamic eggs of Daphnia are formed upon the same 

 type, and consist of the same parts, as any other egg. My object 

 in undertaking the investigation of which the present paper is the 

 result, was to determine whether the same held good of the agamic 

 eggs or pseudova of Coccus, Cynips, and other insects. This inquiry 

 was more interesting, because Prof. Huxley had found several dif- 

 ferences between the ovarian products of the oviparous and vivipa- 

 rous Aphides ; and because, according to Prof. Leydig, the develop- 

 ment of the pseudova in Coccus was extremely peculiar. 



My examination of Coccus was concluded, and the results com- 

 mitted to paper, in the early part of June last, but I then found that 

 so little was known, especially in this country, about the develop- 

 ment of insect-eggs generally, that I withheld my notes from publi- 

 cation, in order to add to them some account of the process of true 

 egg-formation in the Insecta, which would enable me to point out 

 more satisfactorily the differences between, or the identity of, these 

 two processes. 



In all female insects there are two ovaries, each consisting of at 

 least two egg-tubes opening into a common chamber, the uterus. 

 The egg originates and attains to nearly its full size in the egg-tube, 

 and it is therefore with this portion of the generative organs that 

 we are now mainly concerned. 



