188 
POPULAR SCIENCE REVIEW. 
the French Government to send out the Travailleur again this summer on a 
dredging expedition ; this year the scene of her labours will be the Medi- 
terranean. 
The Crustaceans referred to above are described by Prof. Milne-Edwards 
in the Bulletin of the Museum of Comparative Zoology in Harvard College, 
Vol. viii., No. 1. 
Terrestrial progression of CaUichthys. — According to Mr. Joseph Mawson 
of Bahia ( Science , December 25, 1880), the Brazilian Siluroid fish, CaUichthys 
asper , is very active on dry land. Mr. Mawson says : — ‘ During the rainy 
season the fish live in fresh-water pools. When the pools dry up in the dry 
season, they bury themselves in the mud, and remain there until the rains 
return the following year. They are noted for overland excursions. It is 
said that they are often met with going from one pool to another. I have 
had six of the fish in a narrow-necked tin of water, with some sand and 
mandioca meal at the bottom, for five days, and they continue active and 
vigorous, especially the smaller ones. These examples measure from 5 to 
10 cm. in length, and I have seen them much larger. I have had them out 
in the garden several times. I find that they move best on smooth damp 
ground, and are embarrassed by sticks or other inequalities. They can jump 
a little vertically, but their progress on land is effected entirely by a quick 
wriggling motion of the body, which is nearly flat upon the ground. The 
paired fins (pectorals and ventrals) are extended laterally, and seem to bear 
little if any weight ; but they move slightly, and appear to serve to steady 
the body. Last night I heard a peculiar sound, and on looking around, I 
saw one of the fish travelling about the room. He had escaped from the tin 
which was in my bed-room, had fallen from the table to the floor, and j; 
travelled along the corridor, about 12 metres (about 40 feet), to the sola. 
I watched him travelling for two hours, during which time I estimate that 
he moved at least 90 metres. Toward the end of the two hours he seemed 
to flag a little, but in the earlier part his method and speed were fairly seen. 
He seemed to start with a sudden movement of the head or the barbels, 
then wriggled briskly for 5 to 10 seconds, advancing about a metre. Then 
he would rest for about 10 seconds, and start as before. This was kept up 
during the whole two hours, and I left him still moving. This morning, five 
hours later, I found him dead. While he was moving I spilled some water 
on the floor, but he crossed it ; hence I concluded that it was mud rather 1 
than water of which he was in search.’ 
Trichinosis. — The spread of Trichinosis in American pigs is producing jl 
very serious consequences, not only in North America, but also in Europe, 
owing to the great importation of pork, hams, &c., from the United States. 
In France considerable alarm prevails, and the most opposite opinions seem 
to be held — some writers maintaining that ordinary salting is sufficient to 
destroy the Trichina ?, whilst others declare that salting, smoking, and even 
ordinary cooking, will not give the requisite safeguard. M. J. Chatin 
( Comptes Rendus, 28th February, 1881), declares that the examination of the 
encysted Trichinae in salted provisions seems to show that these parasites 
are in a state of absolute functional integrity, for he says, * We know that 
their passage from latent life to death is regularly manifested by important 
modifications in the nature of the cyst ; fatty matter accumulates rapidly, V 
