Reviews—Etheridge’s and Jack’s Australian Oatalogue. 48 
have been described from any deposits referable to the Old Red 
Sandstone period, although rich in the remains of Vish and some 
Crustacea, while the few casts of Mollusca from the Permian beds 
of the County of Dumfries are regarded as no more than mere 
derived Carboniferous fossils. 
The history and progress of Scottish Silurian Conchology is suc- 
cessively treated from the first record of fossil shells by Dr. Hutton 
in 1795 to the present time, a critical analysis being given of the 
relative importance of the works relating to the subject. Much, 
however, remains to be done in the systematic description of the 
shells from the N.W. Highlands, the Pentlands, Kirkcudbrightshire, 
and Girvan, the latter locality yielding to the researches of Mrs. 
Gray during some years the most complete series of Silurian fossils 
ever brought together in Scotland, some of which have been noticed 
by Messrs. Gray, Young, and Davidson. A monograph also on the 
Girvan fossils has been partly published by Prof. Nicholson and the 
author (see Grou. Mage. 1880, p. 189), which important work Mr. 
Etheridge has the modesty not to allude to in his address. 
By far the larger portion of the address (pp. 29-90) is occupied 
with the conchology of the Carboniferous strata, which has been 
studied in Scotland with much greater assiduity than that of her 
Silurian rocks. This may be partly due to the greater and varied 
facilities which the Carboniferous rocks afford for obtaining fossils, 
and their better state of preservation. A detailed notice of the 
various contributions connected with the literature of the Carbon- 
iferous mollusca, from the earliest published remarkable work of 
Ure in 17938, is followed by a systematic review of the different 
classes of Mollusca. This portion of the address is full of valuable 
information, and, while fully acknowledging the labours of other 
authors, Mr. Etheridge brings his own practical experience as to the 
nomenclature, modifications, and affinities of the different generic 
forms, and thus affords an exhaustive analysis of the present state 
of the Carboniferous Mollusca of Scotland, while remarking, “There 
is really more good work to be done amongst the Bivalves and 
Univalves than in any other group of fossil organic remains known 
to us.” Among the interesting notices are those relating to the 
Pectenidz, Aviculopectenide, Mytilide, and Anatinide among the 
Bivalves; the Naticide, Loxonema group, Euomphalide, Pleuro- 
tomariidz and Bellerophontidee among the Univalves; with regard 
to the latter family, including Bellerophon and Porcellia, Mr. 
Etheridge concurs with De Koninck and Meek in placing it near 
Haliotide rather than under the Heteropoda. Under Pteropoda the 
structure, affinities and zoological position of Conularia are fully 
noticed. The characters and subdivisions of Orthoceras, Goniatites 
and Nautilus are severally described. Many interesting points are 
noticed as to the grouping, abundance and rarity of species in 
certain zones, the varietal tendency of some forms, the continuity of 
species, their geographical distribution, colour markings, and stunted 
growth in some localities. 
The geological distribution of the Mollusca is a subject of some 
