402 Mr. J. S. Baly on new Genera and Species of Gallerucidse. 



latter swims with its small, and the former, Vorticella-Yike, with 

 its large end foremost. 



There is no lorica in Urocentrum ; and, according to Prof. 

 Clark, its surface, excepting the crown, is scattered over with 

 small cilia, in which it further differs from Peridinium — where, 

 on the other hand, there is a distinct lorica, and cilia only on 

 the anterior border of the cinctum. 



These are some of the chief differences between the two or- 

 ganisms, of which the most distinguishing are first named. 



It is not my object here to go further into the detail of Uro- 

 centrum Turbo, nor am I prepared to enter the lists with Prof. 

 Clark respecting its organization. 



My observations were for the most part made cursorily, on a 

 supply of this animalcule which I found here in a freshwater pool 

 partly filled with decayed leaves, in July last ; but, seeing that 

 the vesicula (contracting vesicle) was particularly active, I 

 availed myself of the opportunity of watching it carefully with 

 reference to the question whether it threw back into the body 

 or discharged externally its contents, and noted down — (1) that 

 from a simple globular form it became surrounded with a chap- 

 let of ten (?) small globular sinuses ; (2) on these disappearing, 

 the vesicula became still more enlarged, contracted, and in its 

 turn disappeared ; and (3) that immediately after this, one or 

 two vesicles became visible, which, breaking into each other, 

 gave place to the globular form of the vesicula again, to be fol- 

 lowed by the same series of changes, and so on, — still further 

 convincing me that the contents of the vesicula do not return 

 to the body through the sinuses, but are probably ejected from 

 it through the cuticula direct, or through some excretory chan- 

 nel—in this instance close to the posterior extremity, where 

 the vesicula and probably the anal orifice also, are situated. 



Urocentrum was also formerly confounded with Cercaria by 

 Nitzsch and Bory; but the improved quality of our modern 

 microscopical instruments no longer admits of such a mistake. 



Budleigh Saltertou, Devon. 

 Nov. 7, 1865. 



XLV. — Descriptions' of new Genera and Species o/* Gallerucidse. 

 By J. S. Baly, P.L.S. 



Subfam. Halticin^:. 



Genus Diamphidia, Gerst. 



Diamphidia vittatipennis. 



1). oblongo-ovata, convexa, sordide fulva, subopaca, antennis, plaga 

 frontali, oculis, thoracis maculis septem (4 . 3 dispositis), scutello, 



