02 



however, the reno-pericardial openin*^^ neither in Glcba nor in Cymbuliopsis. Gegenbaur and 

 Peck have equally sought in vain for this opening. The pallial cavity of most of the specimens 

 of Cymbuliopsis at my disposal being in a very damaged condition, I have not ventured to 

 sacrifice the only type-specimen of Cymbuliopsis Intermedia, that I might perhaps discover this 

 opening. In Gleba I did not succeed in finding it, notwithstanding many attempts. 



In this genus, however, I have found an opening {e) in the mande, at the right side. It is 

 oval and surrounded by a sphincter; the pallial cavity communicates through it with the exterior. 

 The presence of this opening seems to me quite unique; I could not discover in literature 

 any mention made about it. — The heart "hat so ziemlich die Gestalt eines Kartenherzens" as 

 Gegenb.\ur already said. On its walls, as on those of the wide aortae, large nuclei are distinctly 

 visible. Gegenb.vur mentions three vessels proceeding from an aorta, I have seen only two of 

 them (««?!, ao,y, and an auricle I did not observe at all. Readily admitting the incompleteness 

 of my description of the excretory and circulatory organs, I hope, however, to take these 

 studies up again as soon as possible. 



About the o-enerative organs I can scarcely mention anything. For it is a peculiar 

 fact that any trace of a gonad, of accessory genital glands and even of a penis, is entirely 

 wanting in some specimens. The lack of a penis has already been recorded by Peck. The 

 CTonad is distributed over the visceral nucleus as a thin sheet. As to the genital duct and the 

 accessory glands, I could not observe anything with some certainty. Gegenbaur's description, 

 and especially his figure of the generative organs in Gleba, seems a priori somewhat strange. 



The central nervous system resembles very much that of Cymbulla. The number 

 and disposition of the ganglia is the .same (figs. 115— ii 6). The cerebral ganglia (r) are 

 elongated; at their anterior side a segmentation presents itself, which is more clearly marked in 

 Gleba ; at their posterior side a globular swelling is visible in Cymbuliopsis, while in Gleba this 

 swelling is divided into two or, stricdy speaking, three smaller ones. As Pelseneer already 

 remarked, nerves do not proceed from these swellings. The cerebral commissure is extremely 

 long, and distincdy separated from the cerebral ganglia. The arrangement of the pedal (/) and 

 visceral ganglia [v. p. v.) is quite similar to that in Cymbulla. A small anterior pedal commissure 

 is ecjually found here. The posterior visceral ganglion is somewhat larger than the two lateral. 

 According to the figure of Peck the three visceral ganglia are of the .same size. The nerves 

 arising from the ganglia are disposed in exactly the same manner as in Cymbulla, at least as 

 regards the pedal and visceral ganglia. — From the anterior side of the cerebral ganglia 

 only two nerves issue (not three as in Cymbulla). Both these nerves arise from the ventral 

 .segment. The more ventral (i) which is the stronger and somewhat swollen at its ba.se, 

 supplies the tentacle, a very thin and slender nerve (2) goes to the penis. This latter nerve 

 does not .seem to have been perceived either by Peck, or by Pelseneer. The first author 

 mentions two cerebral nerves of which the dorsal supplies the tentacle, while the other 

 innervates the proboscis. I cannot agree with this explanation, for according to my investi- 

 gations, the nerve to the probo.scis proceeds trom the pedal ganglion. Pelseneer has only 

 made reference to the tentacular nerve in Gleba. — The pedal ganglia give origin to the same 

 nerves as in Cymbulla: two large nerves (4,5), ramifying widely into the fins (fig. 117), issue 



