PREFACE. ix 
ORDER IX. INSECTIVORA—INSECTIVORES. 
Fam. 1. Soricida—Shrews. 
Fam. 2. Talpidz—Moles. 
Fam. 3. Solenodontide 
ORDER X. CHIROPTERA—Bats. 
Fam. 1. Vespertilionida—Common Bats. 
Solenodonts. 
Fam. 2. Noctilionide—Large-eared Bats. 
Fam. 3. Molossidae—Free-tailed Bats. 
Fam. 4. Natalida—Funnel-eared Bats. 
Fam. 5. Phyllostomatide—Vampire Bats. 
ORDER XI. PrimateEs—PRIMATES. 
Fam. 1. Callitrichide—Marmosets. 
Fam. 2. Cebidae—Prehensile-tailed Monkeys. 
The measurements of the species and races, unless otherwise 
stated, are given in millimeters, and usually from some selected 
specimen, although occasionally an average of several examples is 
recorded. But it must always be remembered that the dimensions 
of animals, even of adults belonging to the same species, vary 
greatly, and there is no hard and fast rule by which the exact size of 
any species or race of Mammals can be fixed, and allowance must be 
made for this variability when a comparison is instituted between the 
measurements given and some specimen in hand. It is really not 
easy to find two mammals exactly alike in all their dimensions. This 
fact was emphasized in the Preface of the ‘“‘Synopsis,’’ but it seems 
necessary to repeat it here. 
The illustrations of the Crania exhibit the characteristics of 
every genus and subgenus contained in the work, with but few excep- 
tions, and the Institution to which each specimen belongs and the 
catalogue number is given in every instance. The reason for an 
exception in the list is that it was not possible to obtain the cranium 
when desired, as no example was procurable from any collection in 
this country. These illustrations in half-tone of crania, with the 
exception of a few kindly furnished by the Director of the National 
Museum, were made from photographs taken by Mr. C. H. Carpenter, 
the Head of the Photographic Department of this Institution, and as 
faithful representations of the subjects exhibited with often minute 
and intricate details they will, it is believed, compare favorably with 
any heretofore published. The tooth-rows were photographed by 
means of an especial photomicrographic lens which causes the most 
minute enamel folds to be clearly visible. 
The geographical distribution of many of the species and races 
included in this work is very imperfectly known, as a considerable 
number have been described only within a comparatively short time, 
and consequently but little information has been received regarding 
