226 PHYSIOLOGY OF THE INVERTEBRATA. 



Other species of uEolosoma contain various coloured oil- 

 globules, showing the presence of different pigments in each 

 case. These pigments differ considerably in their capacity 

 for oxygenation and deoxygenation — hence the reason of 

 Beddard's remark: "That the orange-brown pigment of 

 JEolosoma quaternarium and the bright green pigment of 

 ^olosoma variegatum and Headleyi may be less perfect as 

 respiratory pigments, and therefore in course of degenera- 

 tion." 



Although chlorophyll is absent in Phyllodoce, Pontohdella, 

 and j^olosoma, certain Annelids contain this pigment. 



Chcdopterus is one of these animals containing chlorophyll, 

 as shown by Prof. Ray Lankester, whose investigations have 

 been subsequently confirmed by Dr. MacMunn. The alco- 

 holic solution of this pigment possesses a red fluorescence, 

 and gives all the chlorophyll bands, and yields "modified" 

 and " acid " chlorophyll, as well as phyllocyanin, by suitable 

 treatment. There is no doubt that Chcetopterus insignis 

 contains a true chlorophyll, although it may be remarked 

 that Prof. P. Geddes could not detect any evolution of 

 oxygen on exposing Chcetopterus Valenciennesii to sunlight; 

 but this is not to be wondered at, since the chlorophyll is 

 shut up within the animal's body (MacMunn). 



A large number of the Annelida contain hsemoglobin, 

 as shown by Lankester and others : among these may be 

 mentioned the following: Arenicola, Lumhricm, Terebella, 

 Cirratulus, Nereis, and Aphrodite. In the last-mentioned 

 genus the haemoglobin is limited to the ventral ganglia. Id 

 Polynoe, the area round the cerebral ganglion is of a red 

 colour. According to MacMunn this pigment showed a band 

 which somewhat resembled that of reduced haemoglobin. 

 Many of the Annelida are also rich in the pigments known 

 as lipochromes. 



There is no doubt that in this class of animals respiration 

 is greatly aided by various respiratory pigments. 



