854 The American Naturalist. [September, 
Norr. Since this was written Mr. W. T. Swingle has discovered 
that our own Atta tardigrada has the same habits as its South Ameri- 
can relatives, Several fungous gardens have been taken from nests 
near Washington, and the writer has seen beautiful Kohlrobi tufts 
growing on the dung of leaf-eating insects. Erwin F. SMITH. 
ZOOLOGY. 
Irish Fresh-Water Sponges.—In a recent number of the Irish 
Naturalist (Vol. iv, pp. 122-131), Dr. R. Hanitsch enumerates six 
species of Spongillidæ from Ireland, the “ British fauna ” containing but 
four species. Three of these occur in Ireland, the other three sponges, 
all from the west coast of the latter country, being also North A meri- 
can species. Dr. Hanitsch would not solve this interesting distribu- 
tional problem by supposing a former extension of the sponges over 
the whole northern hemisphere; he believes that their gemmules could 
readily have been carried across the Atlantic by winds, ocean currents, 
or birds. In some remarks on the European distribution of the Spon- 
gillide, Dr. Hanitsch notices their extreme rarity in southern Europe. 
Only one species is known from the Iberian peninsula (N. Portugal), 
two from the Italian, while none at all have been found in the Balkan. 
(Natural Science, July, 1895.) 
Reproduction of the Edible Crab.—Through the observations 
of Mr. Gregg Wilson, some new facts have been brought to light con- 
cerning reproduction in the edible crab (Cancer pagurus) of the North- 
umberland coast, England. Crabs that have recently cast their shells 
have pale ovaries that show no development of ova to the naked eye. 
Hard crabs have brilliant orange or scarlet ovaries, with ova distinctly 
visible. Both lots are taken in the catch from October to February. 
Spawning seems to take place only every second year of the crab’s life. 
At no time were ova undergoing segmentation found within the crab, 
so that the old idea that fertilization is internal must be abandoned. 
Milt is undoubtedly passed by the male crab into the body of the fe- 
male, but it does not affect the roe before extrusion. It is received in 
flask-shaped receptacula seminis, that open off the oviducts quite near 
the genital apertures. They are well-valved and seem to retain the 
motionless spermatozoa for long periods. Spawning was noticed to 
