778 The American Naturalist. [September, 
5. That my definition” of the Multituberculata (1) omitted some 
of the characteristic features of this group, and (2) embraced accu- 
rately the genus Mastodon. I find that my definition included 
the only three distinctive and universal characters of this group 
which were known at the time (1888) ; in fact, no additional char- 
acters have since been published, nor are any mentioned by the 
author of the “ Note.” No one, except the author, could confuse 
my definition with that of the Mastodon, because the Multituber- 
culata was placed as a suborder of the Marsupialia. The best 
criterion of the clearness and sufficiency of this definition is that 
the term defined has been universally adopted in subsequent 
official and standard publications (see Flower, Lydekker, Troues- 
sart, Doderlein, Ameghino, and others). 
6. That I overlooked the strong probability that the type of 
Bolodon is an upper jaw of a species of Plagiaulax, and made it 
the type of a new family. The fact is, that so far from overlooking 
the resemblance between Bolodon and Plagiaulax, I have given 
the fullest discussion which has ever been published ™ of the 
evidence for and against the union of these forms into one genus 
and family. The author, moreover, does not mention that the 
latest expression of opinion upon the subject is his own, and in 
favor of the very views he is here criticising, as shown in the fol- 
lowing sentence: “These fossils evidently belong to the family 
named by the writer (¢.¢., by Marsh) the Allodontide, which 
includes the American genus Allodon,and Bolodon from the Juras- 
sic of England.” 
7. That I have overlooked the probability that the type of 
Stereognathus is an upper jaw, although heretofore described as a 
lower one. Nothing can be said in support of such a proba- 
bility. The universal opinion of English writers, following the 
exceptionally careful figures and descriptions of Charlesworth 
and Owen, is that this type is a lower jaw. I have not examined 
9 Op. cit., Fig. 29. 
10" Mesozoic Mammalia,” P. 213. 
1‘ Mesozoic Mammalia,” p. 217. 
VA. C. Marsh, Amer, Jour. Sci., p. 179. See also same journal, April, 1887, p, 329. 





