ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 33 



mantles of snails with dark shells thau in those of snails with light- 

 coloured shells. 



He now extends bis observations to dogs and cats. Again tbere 

 seems to be correlation. The liver and the skin of the animals with 

 dark bair contain almost twice as much iron and pigment as those with 

 light hair. 



Blue and Green Coloration in Skin of Vertebrates. * — Messrs. 

 Camichel and Mandoul have made a physical study of some of the blue 

 and green colorations familiar in mackerel, dragonet, frog, lizard, throat 

 of casuary, snout of mandrill, &c. The blue coloration is due to a 

 black pigment, and analogous phenomena can be obtained from Chinese 

 ink and the like. In the case of tbe green colorations, there is a 

 yellow pigment in addition to the black one. It is suggested that the 

 value of tbe coloration is as a screen which admits useful rays, but is 

 impermeable to those which would injuriously affect the skin. In short, 

 tbe coloration is functionally protective. 



Cervical Glands of Marsupials. f — James Johnstone has examined a 

 young male of a species of Dendrolagus and a male of Acrobates pyg- 

 mse-us, in order to find out whether the peculiar superficial cervical 

 thymus, described in certain other Diprotodonts, is also present in these 

 cases. In the first-named, he finds that the cervical thymus is large and 

 two-lobed ; it exceeds in size the typical thoracic thymus. In Acrobates, 

 the organ appeared to be absent, but close examination showed that it 

 was bound up with a portion of the sub-maxillary, being enclosed in the 

 same sheath as this gland. Comparing these cases with those of other 

 marsupials previously examined, it appears certain that in Diprotodonts 

 generally this cervical thymus is present, while in Polyprotodonts, as in 

 other mammals, it is absent. Too little is known of tbe development of 

 the cervical thymus to make it possible as yet to draw any general 

 conclusion as to the meaning of its presence. 



Parafibula in Marsupials. J — Dr. A. Banchi has previously described 

 in various Lacertilians a skeletal element whose primitive position is on 

 the external side of the fibulo-femoral articulation. Ho finds distinct 

 evidence of the same in the embryos of two Marsupials, Pseudechinus 

 archerii and Halmaturus tlietidis, and in the young of Macropus anti- 

 lopinus. 



Hibernation of Bats.§ — H. Eulot finds (1) that the proportion of 

 water in the body increases from November to April, though there is 

 absolute loss, especially towards the end of the hibernation ; (2) that 

 the absolute and relative weight of fat diminishes through the winter, 

 most rapidly in the later months ; (3) that the same is true for glycogen 

 from November to March, with a slight increase in April, but the 

 quantity is too small to form an important nutritive reserve ; (4) that 

 the consumption of proteids is almost nil in the first months, that it is 

 more considerable in the later months, and that the relation between the 

 quantity of proteid used up and the quantity of fat consumed increases 



* Comptes Eendus, exxxiii. (1901) pp. 826-S. 



f Proc. Liverpool Biol. Soc, xv. (published 1901) pp. 351-62 (3 figs.). 



X Anat. Anzeig., xx. (1901) pp. 273-83 (10 figs.). 



§ Arch. Biol., xviii. (1901) pp. 365-75. 



Feb. 19th, 1902 D 



