Mr. R. F. Tomes on some neiv Vespertilionidse. 335 



Its posterior portion rises nearly at right angles from the termination 

 of the nasal hones, is narrowly triangular, and ends in a point near 

 the top of the elevated part of the cranium. Its anterior portion is 

 nearly horizontal in position, and is deeply cleft in the middle by the 

 nasal bones, which extend backwards as far as to the ascending part. 

 What may therefore be called the facial part of this bone is divided 

 into two 'forks, extending one on each side, between the nasal and 

 maxillary bones. Each of these forks is somewhat swollen, and 

 this, with a great depression along the line of vinion of the nasal 

 bones, gives a deep longitudinal groove to the facial part of the cra- 

 nium, which however becomes nearly obsolete at the nasal opening. 



A great peculiarity consists in the development of the intermaxil- 

 lary bones. These are not cleft in front as in FespertiUo (leaving 

 only space enough for the incisors to be placed close to the canines, 

 and in a line nearly continuous with them), but are united, leaving 

 only two small incisive foramina in the anterior part of the palate. 

 Also they differ materially from the same bones in the genus Vesper- 

 tilio, in having the upper free margins, forming the walls of the nasal 

 opening, continued without any diminution of their depth to their 

 most anterior point. The upper margins of these bones are usually 

 very much sloped in the genus Vespertilio. 



In consequence of the great degree of development of the inter- 

 maxillary bones, abundant space is allowed for the incisor teeth. 

 Accordingly there is a considerable interval on each side between 

 them and the canines, and they are arranged, not in a line with the 

 rest of the dental series, but verticaJhj and in a regular cur^e across 

 the extremities of the above-mentioned bones. There is however an 

 interval in front, between the central ones, though not so consider- 

 able as the space contiguous to the canines. 



Their form is that of a short cone, the inner pair vdth their points 

 directed somewhat inwards. 



The canines are of a very remarkable form — a form, so far as I am 

 aware, not hitherto observed in any other mammal. They present 

 four points : a central cusp of the usual canine form, a lobe acces- 

 sory to this, and situated about the middle of its posterior edge, one 

 at the base of the same edge, and one of a very pointed form at its 

 anterior base. The remaining teeth in the upper jaw do not differ 

 materially from those of Vespertilio proper. 



The lower incisors are uniformly arranged and bifid. The canines 

 are small, with an anterior and posterior spur at their bases, the aii- 

 terior one being the longer, and appearing like two additional inci- 

 sors. There are three premolars on each side, conical, and increa- 

 sing in size as they approach the true molars. These latter resemble 

 those of Vespertilio restricted. 



The formula of dentition may be thus expressed : — 



In.|-i C.H P-M-B M-H' totalis. 

 On examining the under surface of the skull, we find that the bony 

 palate does not extend posteriorly beyond the last molar. In this 

 respect it resembles the genus Miniop'teris, whilst in Vespertilio the 



