1889.] NATURAL SCIENCES OF PHILADELPHIA. 337 



phalangeal joints, and the fourth interspace not crossed by fold in 

 three. Bands were absent across the interspaces in four. The post- 

 digital line in the fourth interspace from the joint in one. 



It will thus be seen that the presence of the raised fold in the angle 

 of the third and fourth interspaces is variable in the young of this 

 species and it may be here regarded as a variable, acquired character. 

 In the embryo of P. medius, the fold was present. 



The arrangement of the lines on the membranes is sufficiently 

 distinct to distinguish the single example of Epomophorus from any 

 of the four species of Pteropus. It is evident that in the genus last 

 named the same general characters are declared with a disposition 

 to variation in a few details. 



Cynonycteris collaris. 



The arrangement of lines much the same as in Pteropus. There 

 are six raised intercostal lines present. All the digital lines appear 

 at the joints or the phalanges. The oblique line from the forearm 

 absent in the prebrachium. The raised folds are absent from the 

 angles of the interspaces. 



Cynonycteris aegyptiaca. 



The intercostal lines are rudimentary or absent. The lower or 

 crural line alone weH seen. 



Cynopterus sp? from Borneo. 



A few rudiiuental intercostal lines seen which do not join the 

 trunk. A large pelvo-crural raised line is present. The intercosto- 

 humeral line is raised, simple and without division until the border 

 of the free margin of the membrane is reached. The nerve does 

 not extend as far as the line of the elbow. The internal-cutaneous 

 line with three superior branches. Numerous small vertical lines 

 traverse the mesopatagium. The main nerve sends a branch to 

 the metacarpophalangeal joint of the fifth finger. 



The fourth interspace with digital nerves from the metacarpo- 

 phalangeal joints. The third interspace with the postdigital from 

 distal fourth of the first phalanx. 



Cynopterus sp ? from Borneo. 



No branch is given from the internal-cutaneous nerve to the 

 metacarpophalangeal joint. In other respects as in foregoing. 



Cynopterus sp ? 



The intercostal lines join the body, and are raised. The meso- 

 patagium with numerous vertical lines, at least sixteen in number. 

 16 



