188 bulletin: museum of comparative zoology. 



Colossendeis cucurbita, sp. nov. 



PI. 3, figs. 3, 4; pl.3, fig. 8-13. 



Three specimens (two large and one small) from Station 4647 ; Nov. 9, 1904 ; 

 lat. 4° 33' S. ; long. 87° 42' 30" W. (approximately midway between Aguja 

 Point, Peru, and the Galapagos Islands) ; depth 2005 fathoms ; bottom light 

 gray and brown Globigerina ooze. 



Tj/pe. — Collection U. S. National Museum. 



Specific diagnosis. — Closely related to Colossendeis gigas, but proboscis with 

 an upward curve, and fourth joint of palp longer than second. 



Description. — Trunk moderate for the genus, possibly a little more slender 

 tlian in C- gigus and C. colossea ; no trace of external segmentation. Lateral 

 processes short, considerably shorter than width of trunk ; well separated, the 

 spaces between them ou'ly a little less wide than the processes ; broader distally, 

 and separated from the trunk by a distinct furrow. Across the dorsal surface of 

 the trunk, starting even with the anterior edge of the first lateral processes, is a 

 distinct, broadly V-shaped groove, with its convexity directed posteriorly. This 

 groove marks off the anterior part of the first trunk segment from the remainder 

 of the trunk, which is nearly evenly cylindrical, except that its diameter is 

 greater, both laterally and dorso-ventrally, opposite the second and third lateral 

 processes. This anterior part, or " head," is, however, even broader than the 

 trunk behind it, but is narrowed anteriorly so that its sides are convex, thus 

 giving it a rounded outline as viewed from above. Ventro-anteriorly it is pro- 

 duced slightly for the attachment of the palps and ovigers. Viewed laterally 

 this " head " portion is seen to be bent downward slightly, so that the axis of the 

 proboscis, which arises directly from its anterior end, is depressed at a slight 

 angle from the horizontal plane of the body. 



Caudel segment directed straight backward in the plane of the body. There 

 is a distinct articulation at its point of juncture with the trunk. Length equal to 

 that of the first two coxal joints of the third legs ; as these joints are somewhat 

 shorter in the fourth legs, its tip reaches a little beyond the distal end of the 

 second coxal joint of that pair. Shape slender, slightly clavate, the distal end 

 turned somewhat upward ; greatest diameter considerably less than that of the 

 palps. 



Eye tubercle a low, rounded, transverse ridge situated just forward of the 

 middle of the " head." Ocelli two, small, round, widely separated ; they are 

 marked by a brown pigment which makes them distinctly visible. ^ 



Proboscis one and one-half times as long as the trunk and caudal segment com- 

 bined ; as stated above, it arises directly from the anterior face of the first trunk 

 segment, but is directed slightly downward from the horizontal axis of the trunk. 

 Proximally it is narrow, the breadth being about equal to that of the trunk between 

 the third lateral processes ; this diameter remains nearly constant for about a 

 third of the length, when it expands to nearly double ; in its distal third the pro- 



1 Tliey are much less conspicuous in the small specimen. 



