404 TUBULARIA REGALIS. 



inches, and consisting of clusters of uubranclied stems, which are about one twelfth of 

 an inch in diameter, and spring from a nxDRORniZA composed of " closely tangled 

 knotty root-like tubes ;" peris^vhc " more or less ringed or jointed, sometimes very 

 regularly at intervals of an eighth of an inch, or constricted once or twice, and then 

 again smooth throughout." Htdranth with the tentacles of the distal set about 

 fifty in number, gradually decreasing in length from before backwards, and disposed 

 in three or four indistinctly defined closely approximated verticils ; the hydranth is 

 large, and, when fully expanded, measures from tip to tip of the proximal tentacles 

 about an inch and a half. 



GONOSOME. — GoNOPiioBES in dense pendulous racemes, which surpass the 

 proximal tentacles in length, and are disposed one over the other, so qs to form three 

 or four superposed verticils ; the gonopliores are elongate-oval or piriform in the male, 

 broadly oval or globular in the female ; in both destitute of tentaculiform tubercles 

 and with four radiating canals, which open into a small circular canal which 

 surrounds a perforation near the distal end of the gonophore.' Actintjla with oral 

 tentacles at the period of its liberation. 



Development of Gonosome. — From March to December. 

 Habitat. — Attacbecl to suljmerged bodies in brackish water. 

 Locality. — Massachusetts Bay, Professor Agassiz. 



This fine species is described and beautifully illustrated by Agassiz, from whose account of it 

 I have obtained the characters embodied iu the above diagnosis. It apparently comes near to the 

 Tuhularia indivisa of the European side of the Atlantic, differing from this species chiefly in its 

 more or less annulated stem, the larger size of the hydranths, the more numerous racemes of 

 gonophores, and the disposition of these in several superposed verticils. 



Tiibidaria Couthouii has been studied by Agassiz, who has given us a very valuable chapter 

 on its structure. He has described in its stem a large-celled imperforate axis, and a system of 

 peripheral tubes, similar to those met with in Tubitlaria indivisa. 



*^* 3. TuBULARIA REGALIS, Bocch. 

 T0BULARIA REGALIS, — Boec/c, iu Forhand. Videusk. Selsk Christiania, 1859, p. 115, tab. iii. 



TROPHOSOME. — Hydrocaulus simple, attaining a height of from six to seven 

 inches, and with a thickness of about one eighth of an inch ; ccenosarc exhibiting 

 longitudinal vermilion bands, which are visible through the clear horny perisarc. 



^ In some instances fine radiating canals were observed; plain!}' an abnormal ii-regularity. 



