^"iHufj!"'] PROCEEDINGS OF THE NATIONAL MUSEUM. 3 



Tlie winfi" nicinbraiic above the arm and toreanii is tlic prcbrac.liiuin 

 (iiiitebiacliial mcinbraiie, propatagium). 



The wiiij*' meiiibraiu^ below the arm ami forearm wouhl become anti- 

 thetically the i)ostbriichium. But since the postbrachium could not be 

 separated from the sides of the trunk and the legs, it has been tbuud 

 necessary to discard it. 



The part of the wing membrane lying between the body, the luimerus, 

 the lower extremity, and a hypotheti(;al line drawn downward from the 

 elbow and intersecting the free margin of the membrane, "is the eudo- 

 patagium. 



The boundary at the elbow is often fixed by the vertical terminal 

 branch of the intercosto-humeral line. The subordinate lines (probably 

 platysmal in origin) in the cndopatagium incline obli(iuely either to- 

 ward the humerus or the trunk. 



The part of tlie wing membrane which is limited by the line at the 

 elbow as above given, by the forearm, and the fifth metacarpal bone 

 and phalanges, is the mesopatagium.^ Within the mesopatagium the 

 subordinate lines incline either toward the forearm or the m;inus. 



The part of the wing membrane limited to the nvanus becomes the 

 ectopatagium (dactylo-patagium). The subdivisions of the ectopatagium 

 are the first, second, third, and fourth interspaces. Tliese are named 

 from the pollex toward the <pdntus. The series of bones which is em- 

 braced in the metacarpal and phalangeal lines being conspicuous in 

 the bat, it is desirable to possess a name in referring to each series 

 taken as a whole. The name digit will be used for the rod of segments 

 embracing the metacari)al element. The nerve which appears at the 

 anterior margin of a digit becomes predigital, and thatof thie posterior 

 margin, postdigital. 



The cartilaginous tip to the terminal bony phalanx, respectively, of 

 the third, fourth, and fifth fingers will receive the name of the third 

 phalanx when three phalanges are present, and of the fourth phalanx 

 when four phalanges are present. The shapes of the terminal pha- 

 langes are of interest and some of these will be described. 



I have examined a suflicient number of genera to suggest that an 

 account of the markings of the wing membranes and of the shapes of 

 the terminal plialanges enter into all discriminating studies. 



The division of the wing membrane into the parts endopatagium, 

 mesopatagnim and ectoopatagium is sustained by what is observed in 

 laphozous maiiritiaiius, since in this species the endopatagium is of a 

 dark colm' while the rest of the membrane is white, excepting the extreme 

 tip of the end of the third finger. Now when the animal is at rest the 

 surfaces above named are those only which are exposed to the light. 

 In all young bats which cling to the mother, without exposing any other 

 portions of the membrane than those named, it is evident that for a 



*The endopatagium and mesopatajjjium aro together the same aa plagiopatagium 

 of Koleuati. (Beitr. z. Naturgesch. derEurop. Chir., Dresden, 1857.) 



