358 
Analyses of Books. 
[June, 
On the Structure and Affinities of the Genus Monticulipora and 
its Subgenera, with Critical Descriptions of Illustrative 
Species. By H. Alleyne Nicholson, M.D., D.Sc., 
F.R.S.E., F.L.S. Edinburgh and London : W. Blackwood 
and Sons. 
Prof. Nicholson steadily continues his laborious researches in 
palaeozoology, turning his attention mainly to marine forms of 
life. He disclaims for the present work the title of a mono- 
graph, as it does not even exhaust his own collection of Monti- 
culiporoids. He complains, and with perfect right, of the 
difficulty of identifying many, even typical, species. When using 
a name we are not certain of really dealing with the form so 
named by the original founder of the species. Hence an im- 
mense amount of work remains to be done before palaeozoology 
has definite materials to work upon, and the determination of 
stratigraphical horizons by means of their characteristic fossils 
is —especially as far as the palaeozoic deposits are concerned - 
rendered very untrustworthy. Hence the objeCt of the work is 
to define and characterise forms which have been insufficiently 
described. The illustrations have been chiefly drawn by the 
author himself, and, in all but three or four instances, from spe- 
cimens and slides in his own collection. 
Dr. Nicholson defines the genus Monticulipora , in its widest 
sense, as “ including forms in which the corallum is composed of 
numerous closely approximated tubular corallites, the walls of 
which are never absolutely amalgamated with one another, though 
sometimes apparently so. Walls ofthe corallites imperforate ; 
septa entirely wanting ; tabula always present in greater or less 
number, though sometimes obsolete ; generally ‘ complete,’ and 
approximately horizontal, but sometimes incomplete. The coral- 
lites are sometimes divisible into two distinCl groups, one of large 
and the other of small tubes, the latter usually more closely 
tabulate than the large tubes. The surface often shows, at regu- 
lar intervals, areas raised above the general level of the surface 
‘ monticules,’ or slightly depressed, and then known as maculae.” 
The author then examines the modifications of this general out- 
line as exhibited in the subdivisions of the genus. He shows 
that the nature and disposition of the corallites are not sufficient 
for a basis of natural classification. 
On the development of the group he is unable to agree with 
the conclusions of Dr. Lindstroem. As regards the affinities 
and zoological position of the group, he considers that there is 
no real relationship at all between Heteropora and Monticulipora . 
He then reviews the relation of the genus to the extinCl forms 
Chceteles, Stenopora , Tetradium, Ceramopora, and Heterodictya , 
and proceeds to a consideration of the subgenera and the 
species. 
