822 PROF. G. C. BOURNE ON THE [Nov. 17^ 



and figures a posterior diverticulum of the buccal bulb which I 

 have failed to discover either in sections or by dissection, and 

 his drawing of the salivary glands is incorrect in detail. In 

 describing the heart he has, curiously enough, fallen into the same 

 error as some of his predecessors, since he categorically denies the 

 presence of a rudimentary right auricle : " da von einem rechten 

 Yorhof nicht einmal ein Rudiment mehr erhalten ist." 



After criticizing Perrier's account Bela Haller gives a somewhat 

 detailed description and a figure of the kidney of Xerita ornata, 

 but neither description nor figure is correct. According to him 

 the kidney is an acinous gland, not difierentiated into anterior 

 and posterior lobes differing in histological structure. The duct& 

 of the acini unite and open by large apertures directly into the 

 bladder (Urinkammer). The reno-peri cardial canal opens into 

 the bladder and is dilated into a large sac which runs back 

 posteriorly between the pericardium and the ureter, and is- 

 identified with the cavity described by Perrier as lying between 

 pex^icardium and kidneys and incapable of being injected from the 

 general body-cavity. I shall prove, in due course, that the 

 glandular part of the kidney is not acinous, that there is a histo- 

 logical differentiation between the anterior and posterior moieties, 

 that there are not several ducts leading from the glandular part- 

 to the ureter, and that the reno-pericardial canal ojDens not into 

 the bladder but into the glandular portion. 



As for Haller's description of the male and female generative 

 organs, I need only say that his work is scarcely an advance on 

 that of Claparede, and he failed to discover the remarkable com- 

 plexity of these organs, which, indeed, could hardly have been 

 discovered without caiefvil and laborious reconstruction of 

 sections. 



It could not be guessed from the title " Die systematische 

 Stellung der Solenogastren und die Phylogenie der Mollusken "■ 

 that Thiele's (39) memoir, published in 19(J2, contains a number 

 of new and acute observations on the morphology of the Neritacea. 

 Interpolated as they are in a lengthy discussion of the phylo- 

 genetic history of the Gastropoda, Thiele's results are somewhat 

 difficult to summarize, and it is to be regretted that he did not 

 see fit to embody them in a separate memoir. He studied 

 sections of Nerita fica^ Septaria parva and suhorbicularis, Scu- 

 telliiia cinnavwmea, and Helicina japonica. It should be noticed 

 in the first place that he places /Scwie^^Mja without comment among^ 

 the Neritidine. ScuteUina was classified by Fischer (15) among the 

 Docoglossa, by Pilsbry and Tryon (40) near the Haliotidse, and I 

 have been unable to discover what author detected their relation- 

 ship to the Neritidfe. It is clear, however, from Thiele's account 

 of the female generative organs that it belongs to the last-named 

 family. After touching on various points of the anatomy of 

 the [N'eritida?, such as the ctenidium, which he compares with 

 that of the Acmjeidse rather than the Trochidpe ; the subpallial 

 sense-organ, which he describes and figures correctly but is 



