78 REMARKS UPON APPENDICULARIA AND DOLIOLUM 



two orifices, and the structure of the testis, all indicate a position for 

 Dolioluiii intermediate between Salpa and Pyrosoma. 



Its apparent unisexuality very likely arises from the ova being 

 developed, and leaving the parent in a younger state than any I 

 examined. I have elsewhere mentioned the liability to deception 

 in Salpa from a similar cause. 



Note. — Since writing the above I have found a short notice of 

 Appendicularia in Miiller's Archiv for 1846,'' under the name of 

 Vexillaria flabelluvi. The describer. Prof Midler, confesses that he 

 does not know in what division of the animal kingdom to place 

 this creature ; and his account of its structure is not a little vague, 

 including little more than its mere external appearance. He does 

 not seem to have observed anything corresponding to the " Haus " 

 of Otto. 



DESCRIPTION OF THE PLATES. 



PL. XV. [Plate 5] Salpa. 

 Salpa A. 

 Salpa B. 



Dorsal view of Salpa A, the muscular bands being omitted. 

 Dorsal view of Salpa B, the muscular bands being omitted. 

 Intestinal canal of Salpa A. 

 Intestinal canal of Salpa B. 

 Dorsal view of extremity of Salpa B. 



Part of the respiratory chamber of Salpa B, showing the fcetus suspended. View 

 from above. 

 Fig. 9. Connection of the gemmiferous tube with the heart. 



PL. XVI. [Plate 6] Salpa. 



Young gemnire (Salpa B) attached to the gemmiferous tube. 

 Nuclear end of one of these, showing the ovum and its pedicle or gubernaculum. 

 Nuclear end of a very young Salpa A, just detached. 

 Placenta and gemmiferous tube of this enlarged. 



Heart, placenta, and gemmiferous tube of a young Salpa A, showing the rudi- 

 mentary condition of the last structure. 

 Ganglion, otolithic sac, and languet. 

 Young Salpa A, still attached by its placenta in the interior of Salpa B 



Pl. XVII. [Plate 7] Pyrosoma. 



A single " zooid," viewed from the right side. 



A single " zooid," viewed from above. 



Part of the branchial network. 



The ovum with its pedicle in situ. 



Testis and ovisac in situ, both emptied of their contents. 



Ovum and pedicle. 



A young zooid developed by gemmation. 



^ Bericht iiber einige neue Thierformen der Nordsee. 



