THE AMERICAN NATURALIST. [Vol. XXXVII. 



sandy or muddy bottom. In some localities it is quite plentiful. 

 It has been collected in three different places, all within Massa- 

 chusetts bay." Specimens have been taken off "Crab Ledge," 

 Chatham, in the deep waters of Muskeget Channel and in Vine- 

 yard Sound. The natural position of this hydroid is an upright 

 one. Hargitt (:oi, p. 313) describes this hydroid as "bright 

 pink in color, medusa: light yellowish, manubrium, tentacles and 

 bulbs pinkish." 



Corymorpha is always found as a solitary form, never budding 

 nor giving rise to colonies. The stems grow to a height of from 

 six to ten centimeters and reach a maximum diameter just a 

 little above the proximal extremity. Toward both extremities, 

 the diameter decreases ; the stem tapering gradually toward the 

 distal end, where it terminates in a short blunt point. The stem 

 is invested in a very delicate, filmy, colorless perisarc, which in 

 the upper region of the stem is very closely applied, but below 



here a sort of loose fitting corrugated sac over the blunt point of 

 the basal extremity. The stem is seen to be traversed by a series 



and there, and which represent, as we shall see later, a series of 



of the stem there grows out a large number of short papilliform 

 processes. The hydrorhiza consists of a tangled network of 

 numerous thread-like filaments. 



The hydranth is somewhat flask shaped, the neck of the flask 

 being represented by the flexible proboscis at the distal extrem- 

 ity of the hydranth. In the centre of this proboscis is found the 

 mouth surrounded by from seventy-five to eighty-five closely set 

 tentacles arranged in a number of irregular whorls, and having 

 somewhat the appearance of a brush. About the base of the 



