Allen.] 5^8 [Oct. 4, 



frequently mistaken by anatomists for the whole of the notochord, in the 

 intervertebral regions of the column. It is present in CMmoBra, Acipenser, 

 Petromyzon, Myxine, and traces of it are present in higher types. It may 

 be derived from the primitive central canal of the notochord, or mark the 

 point from whence that canal has disappeared. The partially tubular 

 notochord of Hemichorda would countenance this view as well as the 

 partially hollow notochord (at the caudal region) of the embryos of some 

 birds. 



The writer would here acknowledge the value and importance to him 

 of materials kindly supplied to him from the National Museum at the in- 

 stance of the obliging Director of that institution, Dr. G. Brown Goode. 



On the Genus Nyctinomus and Description of Tioo New Species. 

 By Harrison Allen. 



(^Beacl before the American Philosopldcal Society, October 4, 1SS9.) 



The genus Nyctinomus includes twenty-one species and is of cosmo- 

 politan distribution. Thus ten species are found in Africa and Madagas- 

 car ; one in Europe with a range in the northern part of Africa ; two in 

 India ; two in the Malay Archipelago ; one each in Polynesia and 

 Australia, and four in America. It is interesting to contrast this wide 

 range with that of the other two genera of the group in which Nyctino- 

 mus is found, namely Cheiromeles, which is restricted to the Indo- 

 Malayan subregion, and Molossus, which is confined to tropical and sub- 

 tropical America, excluding the United States. Nothwithstandiug the 

 extended range of Nyctinomus, the species are closely related. With the 

 exception oi N. joJionensis ?i.nA N. australis, few specialized structures are 

 met with ; and but two species — one from Madagascar (iV. albiventer) 

 and a second from Africa (JY. acetabulosus) — depart from a single for- 

 mula for the teeth. As is the case with the Cheiroptera generally, the 

 American species are the most obscure. Of the four described species, I 

 have seen N. hrasiliensis, N. macrotis and JSf. gracilis. A recent study ot 

 the materials at hand has led me to record descriptions of two new 

 species. 



Nyctinomus europs, n. s. 



Muzzle divided in middle into two parts by a vertical linear groove, the 

 sides of which are defined by spines. These are continuous with the 

 spines of the upper border of the muzzle. Ears united over the face for a 



