724 General Notes. 
Professor Osborn regards the Multituberculata as a distinct series, 
and considers their reference to the Monotremata to be an open 
question. the remaining types he refers a part to the Marsupi- 
alia, under the name Prodidelphia (Heckel), and the position of the 
remainder he leaves in doubt, placing them provisionally in the 
Insectivora. The dental characters of the Multituberculata are tole- 
rably uniform, but the case is different with the two other divisions. 
families proposed appear to be well defined. ; 
n analyzing the dental characters, Prof. Osborn follows the lines 
rior and posterior cusps “ paracone ” and “ metacone,” respectively. 
Among Mesozoic Mammalia we have the first three of the above 
types represented, together with a half-prismatic type in Kurtodon 
Osb., besides the Multituberculata. f 
is memoir was long in press, and has grown by a process d 
accretion; hence there appear some unavoidable irregularities 0 
classification of its contents. A foot-note we observe is liable to 
misconstruction (p. 245), where it states that Dr. Harrison Allen 
first demonstrated the modification of the tritubercular into the 
quadritubercular molar crown. Dr. Allen demonstrated the possi- 
This is the almost universal introduction of specific ohana 
into diagnoses of genera. Examples of this are seen on p. 216, 
where all the characters in the generic diagnoses except one or two 
are only specific. b 
This memoir is illustrated by numerous excellent cuts, and by 
two plates. Two of the cuts are here reproduced.—E. D. Cope. 
LYDEKKER ON THE ICHTHYOSAURIA AND PLESIOSAURM n 
In two late numbers of the Geological Magazine of London, ri 
Lydekker publishes reviews of the English species of the 
