ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
425 
but the movements of the animal suggest the mobility of ball-and-socket 
joints ; it follows that the several segments of the legs must move in 
different planes. IIow the movements observed follow from the struc- 
ture is explained by mathematical methods. The relative lengths of the 
different appendages and the segments of these; the angles between 
the various joint-axes ; the muscles of the parts, and so on, are discussed 
in detail. An analysis of the forward walking is given : — thus, the first 
three legs pull while the fourth shoves ; the reverse is true in walking 
backwards. In forward movement, the legs act in order from the first 
to the fourth ; the first of the right acts along with the third of the left 
the third with the first, the second with the fourth, the fourth with the 
second ; the body always rests on six feet. By attaching small pieces 
of sponge wetted with different stains to the ends of the legs, List was 
able to trace out the footprints of the crayfish on land. Through this 
and similar observations he has worked out a very complete account of 
the locomotor movements. 
Brachyura of Indian Seas.* * * § — Messrs. A. Alcock and A. R. Anderson 
have undertaken to name the large collection of shore and shallow water 
crabs recently made on board the ‘Investigator’; 119 species were 
collected, of which it can safely be said that six appear to be new. Of 
the rest 28 seem to be new to the Indian fauna. 
Reproduction of Cancer pagurus.j— Mr. Gregg Wilson thinks that 
there is some reason to believe that spawning only takes place in every 
second year of the crab’s life. The belief that fertilisation is internal 
must be abandoned. It does not appear to have been as yet noticed that 
the sperms that are found in the vasa deferentia of the male crab are 
never free, but always in packets which may be either globular or 
bolster-like. The author has not been able to ascertain how long the 
berries are carried by the mother crab, and indeed little is known about 
the habits of berried crabs. The males are mature when much smaller 
than the females. 
Amphipods of Bate’s and Westwood’s British Sessile-Eyed Crus- 
tacea.! — Mr. A. O. Walker has published what should be an exceedingly 
useful revision of the Amphipods described in Bate and Westwood’s 
well-known work. In this revision Mr. Walker has based his labours 
on the work of Prof. G. O. Sars, and his memoir, though short, is the 
result of much labour. 
Amphipoda from the Tropical Atlantic.§ — The Rev. T. R. R. 
Stebbing describes nine new species of Amphipoda which were obtained 
by the ‘ Buccaneer’ while laying cables on the west coast of Africa. A 
fresh definition is given to the family Scinidae. The author objects to 
the term jumping-legs applied to one pair of appendages by Bovallius in 
the genus Scina. There are some notes on the characters of the Rhabdo- 
somidae, and it is to BJiabdosoma and Scina that all the new species 
described by the author belong. 
* Journ. Asiatic Soc. Bengal, lxiii. (1895) pp. 197-209. 
f Proc. Roy. Soc. Edin., xx. (1895) pp. 309-14. 
X Ann. and Mag. Nat. Hist., xv. (1895) pp. 464-76. 
§ Trans. Zool. Soc. Lond., xiii. (1895) pp. 349-71 (5 pis.). 
