478 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
finds, further, that the leucocytes do not leave the glands by the 
lymphatics only, but that they may reach the blood stream directly by 
diapedesis through the walls of the veins. 
Neomylodon.* * * § — Herr E. Nordenskiold has found some interesting 
remains in the caves at Ultima Esperanza (South Patagonia), from which 
two pieces of the skin of “ Neomylodon Listai ” were previously pro- 
cured. He thinks that the bones he has found, which he promises to 
describe, probably belonged to Neomylodon , and that this somewhat 
shadowy creature was exterminated by some big extinct carnivore, or 
perhaps by the puma. 
Position of Edentata, j — Hr. G. Elliot Smith has made an elaborate 
study of the brains of Edentates, and includes in his memoir a discussion 
of the affinities of this heterogeneous order, as suggested by the anatomy 
of the brain. He does not find that the brain is of the simple and low 
type which has been supposed. The brain of Orycteropus in many 
respects recalls the brain of a simple Ungulate, and the author is of 
opinion that this form is to be regarded as an early offshoot from the 
root-stock of the Ungulata or Condylarthra. The position of Manis is 
more doubtful, but it probably diverged from the primitive stock about 
the same time as the ancestors of the Ungulates. In the American 
Edentates the brain shows affinities, on one hand, with the Carnivora, 
and on the other with the Rodents, and the author believes that they are 
an offshoot from the stock which gave rise to these two orders. The 
paper includes some interesting observations on brain development in 
mammals. 
Affinities of Ornithorhynchus. J — Hr. Y. Sixta gives a detailed 
comparison of the pectoral girdles of Ornithorhynchus paradoxus and 
Uromastix spinifer , pointing out that the skeletal resemblance is so 
strong that even an experienced zoologist might mistake an isolated 
pectoral girdle of the duckmole for that of a lizard. In the embryo- 
logical data as to the development of the girdle in Ornithorhynchus , the 
author finds corroboration of “ the beautiful biological law : — Ontogeny 
is an abbreviated recapitulation of phylogeny.” 
INVERTEBEATA. 
Mollusca. 
Gastric Gland of Mollusca and Decapod Crustacea.i — Hr. C. A. 
MacMunn has investigated the structure and functions of this gland, 
with special reference to the nature and origin of the pigment entero- 
chlorophyll. His conclusions are that the pigment is a derivative of 
chlorophyll, which is taken up from the intestine, dissolved in a fatty 
medium, and is excreted into the tubules of the gastric gland by means 
of the gland-cells. 
Shell-making and the Origin of the Dark Pigment. || — Hr. G 
Steinmann returns to a subject on which he threw some light about ten 
* Zool. Anzeig., xxii. (1899) pp. 335-6. 
t Trans. Linn. Soc. (Zool.), vii. (1899) pp. 279-394 (36 figs.), 
j Zool. Anzeig., xxii. (1899) pp. 329-35. 
§ Proc. Roy. Soc. London, lxiv. (1899) pp. 436-9 (Abstract). 
|| Ber. Nat. Ges. Freiburg i. Br., xi. (1899) pp. 40-5. 
