PHORMOSOMA INDICUM. 157 



Phormosoma placenta Wyv. Thom. 



Phormosoma placenta Wyville Thomson, 1872. Proc. Roy. Soc. Edinburgh, VII, 84, p. 617. 



1874 "Porcupine" Ech., Trans. Roy. Soc. London, 168, pt. 2, Pis. LXII and 



LXIII, figs. 1-8. 

 North Atlantic, from Davis Strait to Gulf of Mexico on the west and from Iceland to 3° N. 



on the east ; 235-1389 fathoms. 



This species is so well known, we need add nothing here to the descrip- 

 tions and figures which have already been published. 



Phormosoma Sigsbei A. Ag. 



Phormosoma Sigsbei A. Agassiz, 1880. Bull. M. C. Z., VIII, p. 75. 1883. "Blake" 

 Ech., Mem. M. C. Z., X, Pis. XII; XV, figs. 3-19. 



Eastern Caribbean Sea ; 120-573 fathoms. 



This species is in life reddish-orange, pinkish abactinally ; preserved 

 specimens are decidedly pinkish-purple when not bleached. Wyville Thom- 

 son says placenta is gray flecked with purple ; preserved specimens are 

 yellowish-brown, sometimes very dark, often more or less bleached. There 

 is no doubt that this species lives in shallower water, ordinarily, than does 

 placenta; the latter is most common at depths ranging from 400 to 1000 

 fathoms, while Sigsbei is found chiefly between 150 and 400 fathoms. The 

 difference in temperature range is even more noticeable, for, while placenta 

 is found only in cold water, 37°-41°, Sigsbei occurs in water ranging from 

 40° to 63°, but averaging about 50°. 



Phormosoma indicum Dod. 



Phormosoma indicum Doderlein, 1905. Zool. Anz., XXVIII, p. 621. 1906. Ech. d. 

 deutschen Tiefsee-Exp., Pis. XV, figs. 1, 2; XXXVIII, figs. 2-2c, 3-Sc. 

 Indian Ocean, coasts of Africa and Sumatra; 257-543 fathoms. 



The large size of the abactinal primary tubercles and areolse is very 

 notable, as they are nearly or quite twice the diameter of those in placenta 

 and bursarium. The color of this species is rather variable, ranging from 

 yellow to dark brown, commonly lighter above than below, and often with a 

 reddish tinge. 



