246 MR. G. E. DOBSON ON SECONDARY SEXUAL [Mar. 4, 



111 his " Critical Analysis of the order Chiroptera " * Dr. Fitzinger 

 has redescribed three species, as Saccolaimus brevicaudatus, S.ful- 

 vidus, and 8. canton, Blyth, which had many years previously been 

 recognized by their original describer (Mr. Blyth) as males of 

 T. longimanus, Hardw., differing from one another in the colour of 

 the fur, length of tail, and in some other points of no specific im- 

 portance, dependent on season, age, and locality. These imaginary 

 species have been relegated by Dr. Fitzinger to the genus Saccolaimus, 

 distinguished by the possession of a gular pouch ; while the females, 

 being without a gular pouch, appear in a separate genus under the 

 names of T. longimanus, Hardw., and T. bicolor, Temm. 



The males of T. melanopogon, Temm., possess a peculiar beard of 

 long black hairs, extending from the angles of the mandible back- 

 wards to the sternum. This beard contrasts remarkably with the 

 rest of the fur, both in the length of the hairs composing it and in 

 their colour. The usual colour of the fur of the animals of this 

 species is white at the base, with black extremities. The hairs of 

 the beard, however, are black throughout, thicker and longer than 

 the hairs occupying the rest of the body. In the females the 

 portion of the body occupied by the beard in the males is thinly 

 clothed with fur not differing from that covering other parts. 



Fig. 6. 



Tapkozous melanopogon. 



The positiou of the beard, and comparative length of the hairs 

 composing it, are shown in the above woodcut (fig. 6). 



Among the Molossi the males of some species are provided with 

 thoracic or gular glandular pouches, which are either wanting or 

 less developed in the females. The thoracic pouch of Dgsopes 

 alecto, an American species, is described by Temminck as follows : — 

 " Plusieurs indiv.dus conserves a l'esprit de vin out servi a nous 

 faire de'couvrir que l'espece est munie au thorax d'une poche ou 

 siphon assez large, couvert par un repli de la peau et conduisant a 

 une cavite pourvue de muscles propres, quiservent a la se'cre'tion d'un 

 fluide onctueux ; le bord inferieur de ce siphon est pourvu d'un 

 bourrelet, et la cavite se trouve en grande partie cache'e par quelques 

 poils assez longs du devant du cou. Les males out cette ouverture, 



* " Kritiscbe Durclisiebt der Ordnung der Flatterthierc,'' Sitzungsber. Wien. 

 Akad. lxi. Abth. i. p. 447 (1870). 



