316 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



prolongation of the canal stripes over the roof of the stomach shows 

 that with growth there have been successive divisions for the four 

 primary canals, the last one being obscured by the lips. In the type 

 specimen there are 38 canals resulting from the bifurcation of the 

 four primary ones (pi. 42, fig. 5). 



As a result of this method of branching the canals are in groups, 

 the number of which varies according to the number of branchings 

 which each main stem has undergone, and the number of canals varies 

 from group to group. In the type the "cross " is so irregular that it 

 is hard to determine which trunks are the four primary ones. But 

 in another specimen, in which the figure is more regular, there are 

 10, 5, 7, and 7 canals, originating from each of the four primary 

 trunks, respectively. In another there are 9, 12, 5, and 8. In the 

 two young aequorids described by Maas, which probably belonged to 

 this species, the central cross is quite regular, and in each specimen 

 there are 32 definitive canals. 



The canal stripes within the limits of the stomach are the visible 

 evidence of lines along which the upper (outer) wall of the manu- 

 brium is now attached to the subumbrella. Between these lines it 

 hangs loose, leaving spaces into which a probe can be inserted or an 

 air bubble injected. Consequently it is easily stripped off, and all 

 the specimens show more or less damage of this sort. 



The manubrium itself broadens as so many sinuses along the suc- 

 cessively formed canals; evidently the outgrowth of new centrifu- 

 gally formed canals takes place from the margin of the manubrium. 

 A still further specialization would be branching of canals outside 

 the margin of the manubrium, such as Haeckel has described. 



Marginal organs. — The tentacles vary in number from about 30 to 

 about 70; the canals from 29 to 46, in specimens 29 to 76 mm. in 

 diameter (1912). Tentacular knobs are numerous; about 110 in a 

 specimen with 29 tentacles. There are usually 1 to 3 otocysts between 

 every 2 tentacular organs ; i. e., upward of 200 [they are so small that 

 the photographs do not show them; but they are easily seen on the 

 specimens]. 



The tentacular bulbs are cylindrical and stout (pi. 42, fig. 6), and 

 do not clasp the exumbrella, though they are truncate basally. In 

 the type some tentacles are opposite canals, some between them (pi. 

 42, fig. 6) ; but in the specimen 36 mm. in diameter, they are all oppo- 

 site canals. 



I have already (1912) called attention to the great length of the 

 excretory papillae borne by both tentacles and knobs (pi. 42, fig. 6). 



Gonads. — The sexual glands are of the usual aequorid type. 



Subumbrella sculpture. — One of the most characteristic features of 

 the species is the presence of conical gelatinous subumbral papillae 



