HARMOTHOE MEXICANA. 57 



setae are widest at the proximal end of the pectinate division from where they 

 narrow distad to the slender acute tip; each bears ordinarily thirty-five to 

 forty pectinae; the smooth tip ends in a slender principal tooth or prong which 

 is nearly straight along its mesal edge and convex on the ectal; the accessory 

 subapical tooth is very short, straight and divergent, and varies considerably 

 in proportionate length and stoutness. In a second type of neuropodial the 

 general form is similar to the preceding but the pectinae are much lower, more 

 like those of the notopodials. The setae of the most ventral series are conspicu- 

 ously different. The yare much shorter and more slender and each distally, 

 beginning at the proximal end of the pectinate division, is strongly curved. 

 Each ends in a slenderly acute and entire tip. (Plate 1, fig. 5-8; Plate 2, fig. 1). 

 The peristomial setae are of the general type of the notopodials. 



The elytra are of the usual number and arrangement. They are moderate 

 in size. In outline they are subrotund, but with the anterior and ectal edges 

 more or less flattened and nearly straight, so that the outline sometimes appears 

 subtriangular with the hypotenuse more convex. Each is densely studded 

 with conical, corneous, and colorless papillae each of which rises from a more 

 expanded, darker, disc-like base. These project from the caudal and ectal 

 edges. No soft papillae proper were detected. Ciha occur sparsely over the 

 entire surface, these projecting sparsely between the papillae of the general 

 surface as well as between the marginal ones of the caudal and ectal edges. The 

 cilia are slenderly cylindrical or distally slightly narrowed, transparent, and of 

 moderate length. The elytrophores are of moderate size. Each presents the 

 usual ear-shaped scar. In position corresponding to that of the elytrophores, 

 there is on each non-elytrophorous somite on each side a conspicuous, stout, 

 conical and light colored process. 



Localities. Off Mexico. Sta. 3425 (lat. 21° 19' N., long., 106° 24' W.). 

 Depth, 680 fms. Bottom of green mud and sand. Bottom temp., 39° F. 18 

 April, 1891. Several specimens. 



Off Mexico. Sta. 3430 (lat. 23° 10' N., long., 107° 31' W.). Depth, 852 

 fms. Bottom of black sand. Bottom temp., 37.9° F. 19 April, 1891. One 

 specimen. 



In lacking large soft papillae on the elytra this species agrees with H. yoka- 

 hamiensis Mcintosh, now known from near Santa Catalina and adjoining islands 

 and from Monterey Bay off the California Coast as well as from Japan, the type- 

 locality. From that species it differs clearly in having the peaks of the prosto- 

 mium very prominent, in the greater relative length of the notopodial setae and 



