410 MARION I. NEWBIGIN. 



while chsetopteriu itself is indefinite in colour and strongly 

 fluorescent, and exhibits a complex spectrum, the action of 

 reagents is to tend to produce pigments of bright definite tint 

 and simple spectrum, which may be soluble in water and are 

 without fluorescence. Certain points of resemblance to 

 bonellin are also of much interest. 



B. Enterochlorophyll. 

 (1) Previous Investigations. 



The name enterochlorophyll was given by Dr. MacMunn (6) 

 to a pigment^ found in the digestive glands of Mollusca and 

 other Invertebrates, which turns green on the addition of 

 acid, and then gives a spectrum resembling that of acid chloro- 

 phyll. The same pigment is apparently denoted by Kruken- 

 berg^s term hepatochrome, but Krukenberg did not isolate the 

 pigment or define it clearly. 



Dr. MacMunn's observations may be briefly summarised as 

 follows: — He found that the epithelium lining the ''liver" 

 tubules in Mollusca contains pigmented oil drops and granules 

 which dissolve in alcohol to form a greenish-yellow solution 

 with strong red fluorescence. The solution gives a spectrum 

 with three bands, one in the red, one to the left of D, and one 

 to the left of E, and also strong absorption of the violet end. 

 In some cases in dilute solution there may be one or two very 

 faint bands in the violet, but these are always ill-defined as 

 compared with the dominant three. The addition of strong 

 acid turns the solution grass-green, shifts the bauds slightly to 

 the right, adds an additional band at the right of the D line, 

 and diminishes the absorption at the violet end, so that one 

 clear band to the left of E is now visible there. It is this five- 

 banded spectrum which Dr. MacMunn compares to the spectrum 

 of chlorophyll. In his first paper (1883) he compares it to the 

 spectrum given by an acidified solution of chlorophyll, — that is, 

 to the spectrum given by a mixture of chlorophyll and phyllo- 

 cyanin j but in the second communication (7) he dwells upon 

 its resemblance to the spectrum of pure chlorophyll. There is 



