EURETE SPINOSUM. 135 



as distinct subspecies. To me it seems that a subdivision of the species into four 

 local forms (A, B, C, and D) adapted to different surroundings, but congenitally 

 hardly at all different, would more correctly express the relation between them. 

 Their distinctive features are the following : — 



Eurete erectum A. {Eurele ereclum F. E. Schulze, 1899). 



Main-tube dichotomous. One kind of scopule with 4-6 end-rays with 

 terminal tyle. Total length of scopules 400-600 m- 



Eurete erectum B. (Eurele ereclum subsp. tubuliferum Wilson, 1904). 



Main-tube simple. Several kinds of scopules with 3-10 end-rays, all with 

 terminal tyle. Total maximum length of scopules 400 fx. Distal ray of dermal 

 pinules under 40 n thick. 



Eurete erectum C. (Eurete erectum subsp. gracile Wilson, 1904). 



Main-tube simple. Several kinds of scopules with 3-6 end-rays. These 

 in some with terminal tyle, in others distally attenuated and without tyle. 

 Total length of longest gastral scopules 1.5 mm. Distal ray of dermal pinules 

 50 M thick. 



Eurete erectum D. 



Main-tube simple. Several kinds of scopules. Some small dermal ones 

 with only 2 end-rays without terminal tyle. The others with 3-6 end-rays. 

 These either distally thickened and with terminal tyle or, more rarely, cylindrical 

 or attenuated distally, without terminal tyle. Total length of largest gastral 

 scopules 1.18 mm. 



Eurete spinosum, sp. nov. 

 Plate 29, figs. 1-26. 



One fragmentary specimen of this species was trawled off northern Peru, 

 west southwest of Aguja Point, at Station 4656 on 13 November, 1904; 6° 54.6' 

 S., 83° 34.3' W.; depth 4062 m. (2222 f.) ; it grew on fine, green mud mixed with 

 gray ooze; the bottom-temperature was 35.2°. 



The lateral rays of its superficial pentactines bear exceedingly large spines. 

 To this the name refers. 



Shape and size. The single specimen is a lamellar fragment 25 mm. long, 

 20 mm. broad, and 2 nun. tliick. It is curved in one direction, the radius of 



