84 General Notes. [January, 
tactile appendage, recalling that ot the anglers, and serving the 
same purpose. Some Bathytroctes, a Stomias with phosphor- 
escent plates, several Malacostei and some Halosaurus live also 
on the same oozy bottom. Many Crustacea, new to science, were 
here dredged, and belonging principally to the group of Galathee 
of the genera Galathodes, Galacantha, and Elasmonotus, whose 
eyes, deprived of any cornea, are covered with an orange colored 
pigment, and should be useless for vision. With them were 
dredged several new kinds of mollusks, among them a Dentalium 
of large size (D. parfait’) and a Pholadomiya. 
Between Senegal and the Cape Verde islands, the bottom, at a 
depth of from 3210 to 3655 meters, consisted of a greenish mud 
rich in life. Some of the animals found there did not differ from } 
those found on the bank situated at the depth of 2300 meters. 
Others presented peculiar characteristics. These were fishes of 
the genus Bathynectes, Synaphobranchus, and Myrus, some 
Aristes, with bright colors and very like those at depths of from 
1000 to 1200 meters, but with smaller eyes. Among Crustacea 
were Pasiphaés, hermit crabs and Myside. Among mollusks 
were a new species of Bulla, and another gasteropod belonging 
to an unknown genus (Oscorys sulcata Fischer); among Echino- 
derms were species of Ctenodiscus, Ophiurans, and species of 
Ophiomusium. 
Between St. Antoine and St. Vincent the fauna surpassed in 
richness any regions previously explored. July 29th, at a depth 
of from 450 to 600 meters, the dredge came up at the end of an 
hour charged with more than a thousand specimens of fishes be- 
longing mostly to the genus Malacocephalus; with more than 
1000 Pandali, 500 amphipods, with long feet, a new species of 
Nematocarcinus, 150 Pasiphaés spotted with red, large carmine- 
red Aristes, and many other forms—7To be continued. 
THE DEPTH TO WHICH SUNLIGHT PENETRATES WATER.—The 
much-di d questi tothe depth to which sunlight penetrates 
water, and the influence which such penetration, or want of pene- 
tration, may exert upon the phenomena of life at great depths 
has attracted renewed attention of late on the part of both phys- 
icists and biologists. The carefully conducted observations of 
Professor F. A. Forel, of Geneva, made upon the Lake of Geneva 
in 1874, proved—at least as far as the resources of photography 
and the human retina permitted—that the limit of absolute dark- 
ness in that lake was reached in summer at the very moderate 
depth of 45 meters, and in winter at 100 meters. Under normal 
conditions of sight a shining object disappeared when immersed 
below 16 to 17 meters. Asper, who continued the researches of 
Forel upon the Lake of Zurich, found in 1881 that photographic 
plates sensitized with bromide of silver emulsion indicated .the 
penetration of light to at least 90 meters. But while the re- 
searches here recorded fix the limit of luminous perception as 
O a Serer sre 
