388 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



Hartlaub says that the characteristic features of this variety are the slender 

 habitus, the fairly subequal shortness of all the cirrus segments, the laterally free 

 division series and second brachials, the shortness of the brachials, the absence of a 

 keel on the first and second segments of the proximal pinnules, the poorly developed 

 combs on the oral pinnules, and a marked difference in the length of the anterior and 

 posterior arms. 



Hartlaub noted that many specimens by their unusually slender build, some- 

 what elongate brachials, and smooth arm bases approach in appearance the very 

 slender Leptonemaster venustus — for instance, one from Barbados. Others show a 

 similarity to the robust var. imlida, which they approach by their pure white color, 

 the shortness of the brachials, and sometimes in the apposition of the division series — 

 as, for example, specimens from Grenada and Dominica. 



The very young individuals of an arm length of about 7.5 mm. show the usual 

 juvenile characters, as the exposed radials. Their cirri are very slender and are com- 

 posed of uniform somewhat elongated segments. Pi is developed, and in the speci- 

 mens from Cape Frio is provided with a very prominent comb. The brachials from 

 the second to the eighth or tenth have either no pinnules at all or only rudimentary 

 stumps, w^hile the eighth, or usually the tenth, and following brachials again possess 

 pinnules of considerable length. On the inner side of the arms the pinnules begin 

 on the ninth brachial. 



The specimens studied by Hartlaub had an arm length of from 7.5 to 10 mm., 

 and about X cirri were developed. Those from French Reef had no pinnules on the 

 third-eighth brachials, while a somewhat larger one without locality [but undoubtedly 

 from Blake station 32] showed stumplike beginnings of pinnules. On the third, 

 sixth, and seventh brachials these are of the same length, while the pinnules of the 

 fourth and fifth brachials are indicated by small swellings. 



Description of the brasiliensis form. — The centrodorsal is small, discoidal, with 

 the bare polar area flat. The marginal cirri are arranged in a single row. 



The cirri are IX-XII, 8-10 (usually 9), rather slender, 5 mm. long. The first 

 segment is very short, the second is about twice as broad as long, the third is about 

 half again as broad as long, and the fourth and fifth are the longest, nearly twice as 

 long as broad. The remaining segments are slightly longer than broad. There 

 is no opposing spine. The terminal claw is about as long as the penultimate segment, 

 or slightly longer, moderately stout, strongly curved basally, but becoming nearly 

 straight distally. 



The arms resemble those of the meridionalis form, and are about 40 mm. long. 

 The distal intersyzygial interval is 3 muscular articulations. 



The pinnules are very slightly carinate, and in general resemble those of the 

 meridionalis form; but P2 resembles P3 and is without a terminal comb. 



The color in alcohol is light purplish brown. 



The preceding description was drawn up from 25 specimens from Cape Frio, 

 Brazil, taken in 64-82 meters. The specimens from Cape Frio mentioned by Hartlaub 

 as referable to var. meridionalis are others from the same lot. 



Localities.— Fish Hawk station 7334 ; off Cape Lookout, N. C. (lat. 33° 57' 30" N., 

 long. 76° 28' 30" W.); 121 meters (5, U.S.N.M., 34641). 



