186 SUMMARY OF CURRENT RESEARCHES RELATING TO 
spawning, development, diet, enemies, diseases, hibernation, &c., and 
gives some carefully compiled statistics. 
Sense of Direction.* — G. Reynaud has made observations and ex- 
periments on pigeons, which lead him to the conclusion that the sense 
of direction from a distance is located in the semicircular canals, and 
has the effect of leading the animal to reverse the path over which it has 
been transported. More precise details as to the experiments are, how- 
ever requisite. 
Openings in the Wall of the Body-Cavity in Vertebrates, f — Mr. 
E. J. Bles finds that there is an interesting and compensating correlation 
in the adult Elasmobranchii, Ganoidei, Dipnoi, some Teleostei, Amphibia, 
certain Ohelonia and Crocodilia, in the development of nephrostomes 
and of abdominal pores. 
Only in some Elasmobranchs are both present ; in most Elasmo- 
branchs, and in all other groups, they are mutually exclusive. In the 
higher Teleostei, in Hatteria, and in some Crocodiles and Chelonians, 
both have been lost. 
Anura hold an intermediate position in so far as the nephrostomes are 
present, but they are not connected with the renal system. The body- 
cavity communicates with the vascular system (1) by the nephrostomes and 
(2) through stomata. The latter alone form a communication between 
the body-cavity and the lymphatic system in the Saurii and Mammalia, 
which have neither abdominal pores nor nephrostomes. 
If stomata were not present in those Teleostei and Saurii which 
have no abdominal pores or nephrostomes, these would form the only 
cases of a closed body-cavity. 
The function of the abdominal pores, like that of the nephrostomes, 
is to void waste products from the body-cavity. In Pisces and the 
lower Amphibia the body-cavity is to a great extent excretory. 
The evidence does not on the whole favour the view that the abdomi- 
nal pores represent a pair of segmental tubes. They seem to be simple 
perforations, and are not necessarily homologous. 
Suprarenal Bodies.f — MM. B. Moore and Swale Vincent describe the 
colour-reactions of the chromogen in the medulla of mammalian supra- 
renal capsules, and show that a chromogen having the same chemical 
nature is present in the paired segmental suprarenal bodies of Elasmo- 
branch fishes. This is an interesting chemical corroboration of the 
conclusion, otherwise arrived at, that the paired suprarenal bodies of 
Elasmobranchs correspond structurally and functionally with the medulla 
of the mammalian suprarenal capsules. 
Suprarenal Capsules in Lophobranch Fishes.§ — M. — . Huot makes 
a preliminary note o.n this subject which he has studied in young 
embryos of Syngnathus Dumerilii. He finds that the structures in 
question arise from two diverticula which appear as external buds on 
the posterior part of the Wolffian duct. The author does not as yet 
make any reference to the fact that the suprarenals of Teleosteans are in 
* Comptes Rendus, exxv. (1897) pp. 1191-4. 
f Proc. Roy. Soc , lxii. (1898) pp. 232-47. J Tom. cit., pp. 280-3. 
§ Comptes Rendus, exxvi. (1898) pp. 49-50. 
