42 



BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



gated Cyclosdlpa jloridana. The large dorsal eye (fig. 17, this page) 

 also is very similar, the only notable difference being that the optic 

 plug is still more intimately fused with the postero-dorsal face of the 

 apical region of the eye. The presence or absence of accessory 

 eyes in the ganglion can not be determined from sections of our 

 poorly preserved formalin material of the young zooids, and it does 

 not seem best to sacrifice one of our two remaining older zooids, the 

 largest yet seen of this species. 



Cyclosdlpa bakeri, discovered by Ritter, has been carefully de- 

 scribed by him. We modify his results but slightly and add little 



Fig. 17.— Cyclosalpa bakeri, aggregated form, an optical section of the 

 dorsal eye, with outline of the ganglion and one neural gland. x 1"5 

 diameters. 



to them except as to the anatomy of the eye of the aggregated form. 

 In the solitary form we find a more complicated arrangement of the 

 atrial sphincters which we find also more numerous than Ritter 

 shows them. In our specimens, the oral retractor runs outside the 

 intermediate muscle and the ventral oral retractor. Ritter shows 

 it internal to them. He omits one sphincter of the lower lip (our 

 first) and shows the connections of the other oral sphincters slightly 

 differently from ourselves. (Ritter directs attention to considerable 

 variation in the aggregated form.) There is an error in his drawings 

 of the solitary form, doubtless inadvertent, though twice repeated, 



