No. 392.] REVIEWS OF RECENT LITERATURE. 671 
The differentiation of the colon is also described. After the return 
of the intestine from its extra-embryonic position, the caecum, which 
marks the cephalic end of the colon, lies in the median plane. The 
caecum then shifts to the left, and the part of the tube extending from 
it to the rectum stretches over the course of the descending colon. 
The growth of the tube in length now carries the caecum transversely 
across the body cavity, thus laying out the course of the transverse 
colon. ‘The tube at last extends caudally on the right side, bringing 
the cecum to its adult position and establishing the ascending colon. 
The coils of the small intestine were also carefully studied, but no 
common type of arrangement could be discovered even in embryos 
of the same litter and of the same size. As the small intestine, hard- 
ened in place in five adult cats, showed no common features so far 
as positions of coils were concerned, it may be assumed that there is 
no regularity in this respect in the cat. 
€ paper is concluded with an account of the changes in bulk 
and form shown by the liver and the probable influences which these 
have on the disposal of the viscera. GHP. 
Regeneration of Arthropod Appendages.' — Readers of Bateson’s 
“Materials for the Study of Variation ” will recall the experiments 
made by him and Mr. Brindley on the peculiarities of the regenerated 
legs of the Blattida. Brindley has continued this work and gone 
over the literature of regeneration in arthropods, and concludes that 
the regenerated appendage follows one or the other of two types: 
(1) In all respects, such as the number of joints and their relative 
dimensions, the reproduced appendage is the counterpart of the 
normal congenital appendage. 
(2) The reproduced appendage differs from the normal appendage 
in certain respects which are constant, and in cases where maturity 
of the animal is attained through a series of ecdyses the special 
features of the reproduced appendage are perpetuated, so that, 
strictly speaking, the animal does not reproduce the normal append- 
age. The chief distinguishing feature of this kind of reproduction 
is that the number of joints present is /ss than in the normal 
appendage. 
Morphology of the Protobranchia. — An interesting account of 
the habits, structure, and development of Yo/dia limatula, Nucula 
1 Brindley, H. H. On Certain Characters of Reproduced Appendages in Arthro- 
poda, Particularly in the Blattide, Proc. Zod. Soc., London, for the year 1898. 
