166 



March M, 1862. 

 President iii tlie Chair. 

 Tlie following paper was read bj Mr. W. M. Gabb : — 



DESCRIPTION OF TWO NEW SPECIES OF PENNATULIDAE FROM THE 

 PACIFIC COAST OP THE UNITED STATES. 



Pennatula tenua. — Elongated, slender. Naked portion between 

 two-thirds and three-fourths the length of the pennate division of 

 the shaft ; elongated, narrow, fusiform, narrowed and bluntly round- 

 ed at the lower end. Widest part, two-thirds of the length from the 

 end ; surftice deeply wrinkled longitudinally, and minutely, in a 

 transverse direction (in an alcoholic specimen.) Back of shaft 

 deeply grooved fi-om the origin of the pinnae to the upper extrem- 

 ity, on each side t)f this groove roughened by numerous rounded 

 papillae, smaller than the polype cells. Pinnae about forty in number 

 on each side on the only specimen I have seen, placed entirely on 

 the front of the stalk, with a groove between them ; narrow at the 

 base, about twice as wide at the outer edge, wdiich is folded, in 

 the larger ones, towards the middle of the series, into a number of 

 wrinkles like a ruffle. Anteriorly, the polypes extend along the mar- 

 gin as far as the end where it unites with the stalk ; posteriorly, 

 there is a half-inch which is naked ; internal support somewhat flex- 

 ible, nearly as long as the stalk, square with rounded corners, taper- 

 ing at both ends to a fine point, spirally coiled at the upper end ; 

 curved into a long hook, with the terminal branch straight, at the 

 lower end. This branch is about as long as the distance of the 

 hook from the end of the stalk. 



Total length 8-5 in., greatest circumference of the naked part of 

 the stalk -o in., length of the same 3-9 in., length along the polypif- 

 erous edge of one of the largest pinnae 2*2 in., width of ditto .6 in., 

 length of internal support, exclusive of curves, 5'7 in., length of 

 lower hook -9 in., greatest diameter of support, -10 inch. 



From Cape Flattery, Washington Territory, in eighty feet of 

 water. Coll. Cal. Academy Natural Sciences. Presented by Dr. 

 Sproat. 



The long slender general form of this species will distinguish it. 

 I have only seen one specimen, which has been ])i'eservod in alco- 

 hol so lonii, that I cannot determine what was the color during life. 

 The whole surface is now of a nearly uniform drab color, somewhat 

 lighter in the protected portions than elsewhere. 



