168 Reviews—Dr. H. B. Guppy’s Geology of Solomon Islands. 
the Thuringian Proterosaurus, although the teeth are not implanted 
in distinct sockets, as was thought to be the case with the latter. 
Since, however, Prof. Seeley has recently shown that the latter 
supposition is incorrect, the alleged difference is non-existent ; and 
the skull of Haptodus certainly appears to present a striking general 
resemblance to that of the Thuringian genus, as far as its crushed 
condition admits of comparison. The second genus, Stereorhachis, 
is described upon the evidence of part of the upper jaw, vertebra, 
and the humerus (Fig. 4). Prof. Gaudry suggests affinity with 
Prof. Cope’s North American genus, Clepsydrops, which is found in 
the same beds as the Actinodon-like Labyrinthodonts. ‘The structure 
of the humerus, with its characteristic entepicondylar foramen, clearly 
shows that this form is a member of the suborder Theriodontia 
(Pelecosauria), and the probability of its belonging to the Clepsydro- 
pide appears very strong. 
We may conclude not only by complimenting the learned 
Professor of Paleontology in the Paris Museum on the issue of 
these two memoirs, but with the hope that the incessant revolutions 
in commerce will ere long render it practicable to work the Autun 
oil-shales at a profit. Rew 
III.—Tur Sotomon Istanps, rHerr Groxoey, etc., by H. B. Guppy, 
M.B., F.G.S., late Surgeon R.N. Pp. 152, with Maps and Two 
Plates. (Swan Sonnenschein, Lowrey & Co., 1887.) 
fae is the companion volume of a work entitled ‘* The Solomon 
Islands and their Natives,” which was reviewed in “ Nature,” 
Dec. 29, 1887. In his larger work the author dwelt on the 
ethnology, climate, natural history, botany, etc., of these Islands, 
and in the one now under consideration, which was published 
simultaneously, he deals with their geological structure and general 
physical features. He states in the preface that the chief value of 
his observations lies in the fact that his collections of the calcareous 
rocks and of the other recent deposits were examined by Dr. John 
Murray in the light of the results obtained by him from the exami- 
nation of the deep-sea deposits procured by the ‘ Challenger” and 
other expeditions, and also in the circumstance that the characters of 
the volcanic rocks were determined by Prof. Judd and Mr. T. Davies 
with the aid of numerous microscopic sections. Mr. H. B. Brady 
has likewise been engaged in examining some of the Foraminifera. 
A type collection of the calcareous rocks and other deposits has 
been placed in the Jermyn Street Museum, and the volcanic rocks 
are in the British Museum. 
Some of the larger islands, like St. Christoval, are mainly 
composed of much altered and highly crystalline volcanic rocks, 
such as (in the order of their frequency) dolerites, diabases, 
diorites, gabbros, serpentines, saussuritic felspar rock, etc. It is 
most probable that the greater number of the seven large islands 
of the group are mainly composed of these ancient and highly 
altered volcanic rocks. The Island of Bougainville, however, would 
