twenty genera occur in the fossil state, two extending as far 
back as the Jurassic strata, and eight being Mesozoic [Proceed^ 
R.S., Feb. 26, 1876. xxiv. No. 170, p. 566]. 
From Mr. Murray’s Report [op. cii, p. 471] we gather most 
valuable data for the geologist. The depths of the sea are 
covered with the following deposits, which have been 
formed out of the reach of the land. 
1. Glohigerina ooze. 
2. Radiolarian ooze. 
3. Diatomaceous ooze. 
4. The Red and Grey Clays. 
The first of these deep sea deposits is represented on the 
land by the chalk; the second and third by the siliceous and 
chertsy accumulations in many calcareous strata, such for 
example as the mountain limestone of Derbyshire ; while 
the last throws light on the mode in which some of the 
red, purple, and grey clays and slates have been probably 
formed, such as the Cambrian and in part lower Silurian 
strata, which are viewed by Prof Ramsay as having been 
formed in land-locked seas, or even freshwater lakes, [Quart. 
Journal Geol. Soc. Lond., xxvii. pp. 250 and 253.] In a 
word, the results of the Challenger expedition in my belief 
will be if possible of greater value to the geologist and 
palaeontologist than to the student of zoology. 
2. Professor Huxley on Geratodus. 
Among the more important special contributions to 
recent zoology is the first instalment of an essay on Cera- 
todus Forsteri, the extraordinary 'baramunda’ of Queensland, 
by Professor Huxley [Proceed. Zool. Soc. 1876, 4 January], 
in which he takes up the investigation where it had been 
dropped by Dr. Gunther in 1871 [Phil. Trans. 1871, Part ii]. 
From the study of the brain, skull, and limbs, he concludes 
that it occupies a curiously central position among the 
Ichthyopsida, being allied on one side to the Amphibia, on 
another to the Chimseroid fishes and the sharks, and on yet 
