Dr. Philippi on the animal of Pileopsis Garnoti. 91 



front and inferior part is easily distinguished from the upper 

 thicker part. Eyes are distinct on the outside of the head. 

 The perfect mantle surrounds the whole shell, presents no 

 incision, no siphon, and between it and the oval foot there is 

 not a single organ to be found. A specimen thrown into spi- 

 rits gave more information respecting the internal structure 

 as the intestines shine through the thin peritoneum. The en- 

 tire hinder space of the body was occupied by the brown liver, 

 as also a part of the right side ; the ramified processes of the 

 liver could be plainly distinguished on it. To the right was 

 situated a reddish organ, probably the ovarium. Above the 

 liver, posteriorly and to the left, is situated the intestinal canal 

 with a convexity directed backwards and bending anteriorly 

 and to the right, it disappears before the right end of the 

 muscle which fastens the animal to the shell ; in front of the 

 liver is moreover situated a white organ, the functions of which 

 I do not venture to indicate ; and in front of this, occupying 

 nearly half the space, appears a cavity, in which an organ with 

 a form closely resembling a folded ruff proceeds nearly par- 

 allel with the intestinal canal, and above is adherent to the 

 peritoneum and is evidently the branchia. I now also suc- 

 ceeded in passing a hair through this hole exteriorly, which 

 even appears in front on the right side before the anal aper- 

 ture in the rather thick border of the mantle, where on more 

 accurate examination I found a small black point. On ac- 

 count of the minuteness of the animal no separate anal aper- 

 ture and branchial aperture can be perceived externally. I 

 could not discover an orifice for the sexual apparatus. After 

 I had found this out it was easy for me to notice on the 

 few shells at my disposal that they are somewhat promi- 

 nent in the vicinity of the branchial aperture. From the 

 irregularity of the shell it requires great attention to discover 

 it. But to what genus does the animal belong ? This is a 

 question which, from the entire want in this place of literary 

 auxiliary means, I am not able to answer. The first thought 

 is on Siphonaria, but as far as I can recollect, the horseshoe- 

 like impression of the muscle is interrupted in this genus by 

 the siphon; in the present species the right arm of the horse- 

 shoe is merely shorter than the left. Moreover the animal is 



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