vol.1.] Torrey. — Hydroida of the Pacific Coast. 47 



Catalogue ('65, p. 196), lias mentioned a species of Tubularia 

 which he calls Thamnoctiidia tubularoides, and which is charac- 

 terized by the "stoutness of the stem and size of the head, 

 surrounded by as many as from thirty and even forty tentacles 

 in large specimens. Found growing profusely on the bottom of 

 the coal barges which bring coal from Benicia to the Pacific 

 Mail Company's steamers at San Francisco." This description 

 is very meagre, but is sufficient, I think, to show that it does 

 not refer to the species I have just described. T. marina is in 

 no sense a harbor species, but grows between tides on the lee side 

 of rocks exposed to the breakers of the open sea. Its head is not 

 noticeably large as compared with T. erocea, and the largest 

 number of tentacles I have seen is twenty-six, on one occasion 

 only. The female gonophores are so characteristic that I feel 

 sure they would have been described in Agassiz's notes had he 

 seen them. I have not seen any hydroid in the bay corre- 

 sponding to his description. 



The nearest relative of this species on this coast appears to 

 be T. harrimani Nutting, from which it may be distinguished 

 by the much smaller number of proximal tentacles, and the 

 greater length of the tentacles of the female gonophores. 



CALYPTOBLASTEA. 



Hydroida with true hydrotheea' and gonotheca?. Gonophores when free 

 usually with otocysts; gonads on radial canals. 



Fam. Haleciid^. 



Trophosome. Hydrotheea? arranged alternately on hydroeaulus, shallow, 

 saucer -shaped, incapable of containing the large hydranths in contraction, 

 margin smooth; hydranth with conical proboscis and one whorl of filiform 

 tentacles. 



Gonosome. Gonophores sporosaes or medusoid. 



Whether the Haleciidae are primitive or highly modified 

 Calyptoblastea is a problem that is at present without an alto- 

 gether satisfactory solution. The hydranth-bearing blastostyles 

 and reduced hydrothecae place them near the Gymnoblastca. 

 The presence of sarcostyles (Diplocyathus Allman) and a row of 

 bosses on the inner surface of the theca are characters of the 

 highly specialized Plumulariidae (cf. P. plumularoides) . Sessile 



