306 



COLOURING MATTERS. 



BOOK I. 



The pigments, to be referred to in this section, occur either dif- 

 fused through the tissues, as in many marine animals, or in the form 

 of granules contained in certain cells or layer of cells, usually dermal 

 or subdermal, sometimes deeper in the mesoderm, very rarely in the 

 endoderm. Such granular mesodermal deposits are frequent in 

 cephalopoda, fishes, amphibia and even lizards. The Chlorophylls and 

 associated 'vegetable' pigments, when present in animals, are always 

 in granules, whether in the striae of the myophane of Infusoria, the 

 tissues generally of Spongilla, the sub-muscular mesoderm of Convo- 

 luta, or the endoderm of Hydra viridis. 



The following is a list of such pigments as have hitherto been described, 

 arranged in the order of the animals yielding them 1 . 



Sub-kingdom. Colouring Matters. 



Protozoa. Chlorophyll. Blue Stentorin. 



Porifera. Chlorophyll. Various other pigments shewing no bands. 



Coelenterata. Chlorophyll, &c. in Hydra viridis and in Anthea Cereus, 



var. smaragdina. 



Actiniochrome in Bunodes crassicomis. 

 Polyporythrin in many simple Anthozoa and some 



Hydroids. 

 Two distinct pigments with characteristic absorption 



bands in Adamsia sp. 



A red pigment with one band in Coenopsammia. 

 Other pigments yielding no bands. 



Echinodermata. Purple Pentacrinin in many species of Pentacrinus. 

 Red Pentacrinin in a species from Meangis Is. 

 Antedonin from an Antedon and a deep-sea Holo- 



thurian. 



Hoplacanthinin from Hoplacanthus sp. 

 These four pigments all have absorption spectra with 

 definite bands, the other pigments obtained from 

 animals belonging to this class yield no bands. 

 Verines. Chlorophyll (?) in Convoluta 2 . 



Bonellein in Bonellia viridis. 

 Other pigments yielding no bands, including a blue 



one, reddened by acids, in a Rhyncodemus sp. 

 Crustacea. Chlorophyll in Telotea viridis. 



Crustaceorubrin in many deep-sea Decapods ; in a Pan- 

 darus infesting Carcharius brachyurus ; in surface 

 Entomostraca. 



Other pigments yielding no definite absorption spectra. 

 Insecta. Cochineal from Kermes cacti. 



Aphidein from an Aphis on the apple. 

 Lac-dye from Coccus Laccae. 



Other pigments not yet examined, or yielding no 

 definite spectra. 



1 This list is compiled chiefly from Moseley's previously-quoted paper (Quart. Journ. 

 of Micr. Sc., 1877, p. 1). 



2 Geddes, "Physiology and Histology of Convoluta Schultzii." Proceedings of 

 tlie Royal Society, Vol. xxvm. p. 449. 



