350 



BULLETIN OF THE BUREAU OF FISHERIES. 



Gonosome. — Female gonophores borne on hydranths that are scarcely aborted, though they may be 

 smaller than the ordinary hydranths. They are rather below the hydranth body than on it, and even 

 may be found straggling dow-ti the pedicel for some distance. The pedicels are sometimes annulated 

 throughout, but are not always so. Male gonophores are borne at the base of the body of the hydranths, 

 which show much variation in the extent of the abortion; some of them are scarcely aborted, some are 

 more so, and some have the tentacles reduced to mere buds. Gonophores are few in number, commonly 

 three, with three chambers, or only two. They stand out ver>' conspicuously almost at right angles to the 

 axis of the hydranth. 



Color. — Hydranths and male gonophores vermilion or pink; female gonophores bright orange-red. 



Distribution. — On the piles of the United States Biu-eau of Fisheries wharf and of the railroad bridge 

 from Morehead City to Beaufort, usually growing on large tunicates; on shells in Bogue Sound, lo feet. 



Congdon reports specimens from Bermudas in which the hydranths bearing the gonophores are 

 entirely aborted, but I have found no specimens of such a nature in this region. 



Fig. 8. — Ettdeitdrium ratnosum (Linnseus). 



A, portion of a female colony; B, portion of a male colony; C. a male hydranth 

 much aborted. 



Some difficulty may be experienced in distinguishing the different species of Eudendrium . It may 

 be impossible to do so from the trophosome alone, because the general appearance is so much the same 

 in each case. We speak of a difference of size, but that is ver>' little to depend on, as, in the case of 

 E. ramosum in particular, there is very wide variation. Though this hydroid may attain a height greater 

 than any of the others, and usually is large when it is found near tide mark, in deeper water the forms 

 dredged may be matiu-e before the height of an inch is reached, at which time this species bears much 

 resemblance to E. capillare, which, on the other hand, never reaches a great height. Mode of branching 

 is a poor criterion upon which to depend, because there is not a definite method in any species, with 

 the possible exception of E. album. The amoimt of annulation will not answer the ptu-pose, because 

 this is not constant, and, in any event, agrees fairly well in the four species under discussion. If the 

 male and the female gonophores can be found in good condition the difficulty disappears. For that 

 reason I have laid special stress on the gonophores in each species. Those of E. ramosum and E. album 

 have the greatest resemblance to each other, but those of E. album are much smaller, corresponding to 

 the minuteness of the species. Besides this, the male gonophores do not stand out at right angles as 



