26 BULLETIN 43, UNITED STATES NATIONAL MUSEUM. 



nominate boue is lightly lield to the sacrum and at the symphysis pubis. 

 The inner trochanter of the femur equals the external. Both are small 

 and the gluteal crest is scarcely larger than a flange which unites the 

 inner trochanter to the shaft, thus making the femur unique. The in- 

 ner condyle is slightly the larger and the notch narrow. The tibia 

 with large projecting median spine at the proximal end; malleolus dis- 

 tinct. 



In Ailelonycteris and Lasionycteris the parts quite as in Vespertilio, 

 the pectineal spine slightly longer; the shaft of the femur just below 

 the head less expanded. 



Corynorhinus much as in Yespertlllo, but the upper part of the femur 

 much less expanded, the shaft near the trochanter scarcely at all. 



The femur is without neck. The outer and inner trochanters are 

 subequal and of large size, the outer tending to become the larger as 

 in the molossines. The outer side of the shaft below the trochanter 

 is often marked l)y a flange in position of the third trochanter. Hip- 

 posideros and all phyllostomines show an inclination to the development 

 of a conspicuous flange on the inner side of the shaft near the inner tro- 

 chanter. This is most marked in Chilonycteris, Mormops, and Natrdus. 

 In the genera last named the trochanters are drawn backward, lie on 

 the posterior surface of the bone, and are in close relation (resembling, 

 with the head, tlie anterior end of a geometric larva), while as a rule 

 they are on lines which answer to the lateral ligaments of the knee 

 ioint. The condyles are approximate markedly unequal with a narrow 

 intercondylar notch, the inner condyle being the larger, as is the rule, 

 or wide apart with small condyles, as in molossines and rhinolophinea. 

 The tibia may be shorter than the femur, as in Ariibeus and MoIossks, 

 but it is, as a rule, longer than that bone. The inner tuberosity is fur- 

 nished with a horizontally-projecting process in vespertilionines ; this is 

 an excellent character defining the family. The tubercle for insertion 

 of the hamstrings is most marked in strictly arboreal forms, as the 

 pteropines. The malleolus is often rudimentary or absent, as in phyl- 

 lostomines and rhinolophines. The fibula is uniformly imi)erfect above 

 save in the molossines, where it is complete, or in Antrozous, where a 

 membranous fillet continues the form of the bone to the inner tuberosity 

 of the tibia.* 



* Since the above sketch was written the skeleton of Desmodm has been examined. 

 I tint! that it bears a close resemblance to other phyllostomines, but is distinctive 

 in the following particulars: The shaft of the radius is joined at its middle by the 

 nlua, which can bo traced, nevertlieless. apparently to the wrist. I say " apparently " 

 for the femur, tibia, and fibula exhibit dispositions to form lateral flanges, and it mny 

 be that the structure in ^('smofZ*;.? is not the reappearance of the lost nlna-shaft but 

 is simply the radius, which here exhibits an unusual form. In any event it con- 

 stitutes a character not seen elsewhere in the order. The flanges of the femur are 

 symmetrical, directed forward, and convert the anterior surface of the shaft into a 

 groove for the origin of the femoral head of the quadriceps extensor muscle. The 

 flange in the tibia and tiltula is single; the two are in contact— to obliterate the 

 interosseous space. 



