12 H. N. MOSELEY. 



green pigment in its appendages as is the case in allied 

 shallow water forms as Phyllodice.^ 



Sabella. — A Sabella obtained from 600 fathoms contained 

 chlorocruorin as do shallow-water Sabellpe.- 



Sayitta. — Several species of Sagitta were obtained, some 

 being very large. The large ones contained an abundant 

 red oily pigment soluble in alcohol, which absorbs all the 

 spectrum but the red and yellow (PL IV, fig. 1). 



Crustacea. 



Crustaceorubrin. — Many deep-sea Decapods of various 

 forms are coloured of an intense scarlet. This is the case 

 both with Schizopods, such as Gnathophausia and Petalo- 

 phthalmos (Suhm), and in the Peneids and Caridids, which are 

 excessively abundant in deep water. The oily red colouring 

 matter of these Crustacea is soluble in alcohol, and is in 

 time entirely removed by spirit from specimens preserved in 

 it. The resulting red solution gives a single broad absorp- 

 tion band in the green and blue (PI. II, fig. H). Addition of 

 hydrochloric acid or of ammonia to the solution does not 

 alter the spectrum. A similar red solution yielding the same 

 spectrum is formed when large quantities of red pigmented 

 surface Entomostraca are preserved in spirit. The colouring 

 matter seems to be identical in the two cases. 



Pandarus. — A red colouring matter, probably the same as 

 the above, was detected with the microspectroscope in a 

 Pandarus infesting a Carcharias brachiurus, which was 

 caught oflf the Kermadec Islands. So small a quantity of 

 the colouring matter was present that the absorption band 

 obtained was faint and not nearly so extensive as that shown 

 by intense solutions from the red decapods. It is probable, 

 however, that the colouring matter is the same (PI. II, 

 fig. 12). 



MOLLUSCA. 



Aplysiopurpurin. — An Aplysia is very abundant on the 

 shore at St. Vincent, Cape Verdes. Its habits are described 

 by Mr. Darwin in his Journal.^ The purple fluid emitted 

 by this mollusc is soluble in alcohol. It yields a broad ab- 

 sorption band in the green and blue, consisting of a darker 

 and a lighter portion in weak solutions (PI. II, fig. 13 a), 

 but entirely black in intense solutions. On the solution 

 being acidified it changes to a beautiful violet, and then 



' E. R. Lankester, ' Journal of Auatomy and Physiology,' vol. iv, p. ] 21. 

 - Ibid., ' Quarterly Journal Microscopical Science,' Nov., 1867. 

 3 ' Darwin's Journal,' 2nd edition, p. G. 



