610 Original Articles. [Oct., 



contains only the two very peculiar genera Desmodus and Diphylla, 

 wherein the teeth are expressly modified into an instrument for tapping 

 the blood of other Mammals. In the young Desmodm six upper 

 incisors are present ; in the adult animal the two outer pairs disappear 

 to make room for the highly-developed medial pair, the inner margins 

 of which meet together and form a most formidable weapon for 

 blood-letting. True molars are wanting altogether in this form of 

 bats, as they have no occasion to masticate their food. The stomach 

 of Desmodus also presents a most remarkable structure, which has 

 lately been described by Professor Huxley,* and is clearly connected 

 with its abnormal diet. The cardiac end of this organ assumes the 

 form of an elongated caecum reflexed upon itself, and is evidently 

 intended to form a reservoir for the blood drained by the Desmodus 

 from the body of its victim. 



Whatever may be the case with regard to the other Vampires, we 

 have the most unquestionable evidence as to the blood-sucking habits 

 of the genus Desmodus, Mr. Darwin having been present when, in the 

 neighbourhood of Coquimbo, in Chili, one of his servants captured a 

 bat of this form actually fastened upon a horse's back. As regards 

 its ally Diphylla, we have similar testimony from Mr. Fraser, who 

 sent home from Ecuador an example of D. ecaudata taken in the act 

 of sucking blood from a man.f The fifth and last sub-family of the 

 Phyllostomatidse consists of Mormops, Chilonyeteris, and the allied 

 form Pteronotus, three genera of which the principal sedes is the West 

 Indian Islands, although some of the species penetrate into the 

 adjoining parts of the continent. They are remarkable for having 

 the end of the tail free, and extended from the back of the caudal 

 membrane. 



We now come to the Insectivorous Bats, without any foliaceous 

 appendage to the nose. These are divided by Dr. Peters into three 

 families, each of which has three representatives in South America. 

 Of the Brachyura or Noctilionidas, as we should prefer to call them, 

 distinguished by the abbreviated tail, which is shorter than the anal 

 membranes, four well-marked genera are met with in this region. 

 The most remarkable of them, and one of the most curious forms in 

 the whole series of Chiroptera, is Diclidurus, in which the terminal 

 caudal vertebras are so modified as somewhat to resemble a bell. The 

 single known species of this form, which is of rare occurrence, has 

 been obtained in Brazil and in Central America. It is, moreover, 

 remarkable for the colour of its fur, which is nearly white — a most 

 unusual character amongst the Mammals of tropical regions. 



The [Molossidae, with their long rat-like tails and swollen lips, 

 are represented in America by species of the genera Molossus^ and 

 Nyctinomus, the former, as restricted by Dr. Peters, being peculiar to 

 the tropics of America. The typical and very numerous family, 

 Vespertilionidaa, is of universal distribution, but presents us with 



* " On the Structure of the Stomach in Desmodus rufus." By Professor T. H. 

 Huxley. ' Proc. Zool. Soc.,' 1865, p. 386. 

 t See 'Proc. Zool. Soc.,' 1860, p. 212. 



