368 



JOHN F. FULTON, JR. 



lias likciwiso reporiod the presence of a yellow lipochrome in 

 the epidermis of Arenicola. Inasmuch as Kacovitza (1895) 

 has shown that the amoebocytes of many polychaet annelids 

 (including Arenicola) carry fatty pigments from the blood 

 and deposit them in the epidermis, the unavoidable conclusion 

 remains that the fatty pigments of Arenicola are 

 derived from food, and transported to the 

 epidermis by the b 1 o o d - s y s t e m . It is worthy of note 

 also that many of the lipochromes are closely allied to carotin, 

 which means that they are derived from chlorophyllous food 

 substances. Further consideration of carotin will be given in 

 the following section (p. 87B). 



5. Arthropoda. 



In the phylum Arthropoda, not only is the blood-system well 

 developed, but there are present, as in the cephalopoda, large 

 chromatophores which facilitate colour change. A vast amount 

 of work has been done upon the pigments of the arthropods, 

 and since it has lieen reviewed very completely by Fuchs 

 (1914, crustaceans), and Biedermann (1914, insects), the writer 

 will limit himself to a discussion of the origin of the pigments 

 in this phylum. 



{a) Crustacea. 



The presence of chromatophores in the carapace of crusta- 

 ceans was first noted by Focillon (1851). The classic work 

 on crustacean pigment, however, is that of Gamble and Keeble 

 (1900) on the colour phases of Hippolyte varians, in 

 which the structure and activities of the chromatophores 

 are described in great detail. The structure of the chromato- 

 phores from other species of Crustacea has been investigated 

 more recently by Franz (1910). The pigments which have been 

 found in the blood of crustaceans are very nearly the same as 

 those found in the molluscs, viz. chlorophyll (enterochlorophyll), 

 lipochromes, carotin, haemoglobin,-^ and haemocyanin. As the 



1 Haemoglobin has been detected in several crustaceans by Regnard et 



Planchard (1883). 



