CAROTINOIDS IN INVERTEBRATES 157 



Sphinx Ligustru, C. Elpcnor, D. Vinula, Papilio Machaon, Ephyra 

 Punctaria, and E. Angularia. 



Krukcnberg (1886) made spectroscopic observations of the pig- 

 ments in the haemolymph of the pupa of several additional species of 

 Lepidoptera, namely, Platisama Cocropia, Tclea Polyphemus, Satur- 

 nia Pcrny'i and Saturnia Pyri. In these cases the haemolymph itself, 

 as well as the alcoholic extracts, showed the lipochrome absorption 

 bands. 



In the case of Saturnia Pyri lipochrome was also extracted from the 

 body tissues. The hamolymph of another species, Collosamia Pro- 

 methia, did not show the presence of lipochrome until first extracted 

 with alcohol. Krukenberg's observations, unfortunately, do not throw 

 any light on the character of the carotinoids present in caterpillars, 

 although they support strongly the idea of a general distribution of 

 carotinoids in the blood and tissues of these herbivorous insects. This 

 cannot be said, however, of the recent extensive study of this question 

 by Geyer (1913). According to Geyer's own conclusions his results 

 are in entire agreement with Poulton's as to the presence of xantho- 

 phyll in the haemolymph of the larvae and pupae of the Lepidoptera. 

 In spite of an acknowledged familiarity with the work of Willstatter, 

 Geyer compared the spectrum of ether solutions of the haemolymph 

 pigments with extracts of yellow flowers obtained with 70 per cent 

 alcohol. Inasmuch as this solvent does not extract the true caroti- 

 noids from plant tissues, it is not surprising that Geyer's spectrum 

 revealed no absorption bands in the blue and green. His blood ex- 

 tracts also failed to show absorption bands, in opposition to the work 

 of Poulton, so that we are still in the dark as to the exact nature of 

 the carotinoid pigments taken up by the caterpillars. This is unfor- 

 tunate because Geyer's work is sufficiently recent to have permitted 

 him to use the technic which would have given the desired information. 



While Geyer's studies are disappointing with respect to the kind of 

 carotinoids present in caterpillars, he noticed an interesting sexual 

 difference among certain species in connection with the pigmentation 

 of the hamolymph. In Bomb.yx mori, the larva and pupa blood of 

 the males was always colorless or very faintly tinted, while that of the 

 females was always a bright golden yellow. Similarly in the females 

 of Xanthia flavago the blood was yellowish green, while that of the 

 males was colorless or very pale yellow. In other species the blood of 

 the females was green, containing both chlorophyll and carotinoids, but 

 the males again showed colorless or nearly colorless blood. Geyer 



