1905.] OF THE GENUS RHINOLOPHUS. 107 
essential points similar to 2A. afinis. It agrees with the now 
existing affinis in the pandurate sella and the prolongation of 
Iii’. But it is considerably higher-developed, chiefly in the 
following respects: (1) the dentition; (2) the wing-structure ; 
(3) the length of the tail; (4) the beginning, or complete, reduction 
of the lateral mental grooves; (5) the general size. 
The peculiar prolongation of the second phalanx of the third 
finger, described above under 2h. affinis, is preserved in Rh. ferruim- 
equinum: III.’ is more than (or, extremely rarely, at least equal 
to) 14 the length of III... Also IV.’ is lengthened, i.e. more than 
14 of IV.’; it is an interesting fact that, in this particular point, 
Rh, ferrum-equinwm (all races) agrees with Lh. affinis himalayanus, 
but not with any of the other races of affinis. Besides these 
two characters, which are simply inherited from an affinis-like 
ancestor, there is an important modification in another part of 
the wing, to which we have no parallel in any of the foregoing 
forms*, viz. «@ change in the proportionate length of the third, 
fourth, and fifth metacarpals, as shown in the subjoined table :— 
3rd meta- 4th meta- 5th meta- 
. Forearm. carpal. carpal. carpal. 
All the foregoime species 
(94 examples) ..................... 1000 715 739 740 
Rh. fervrum-equinum 
(all races; 121 examples) ...... 1000 644. 724) 743, 
This table shows:—(1) In all the foregoing 21 forms of this 
eroup the fourth metacarpal is but very little longer than the 
third (24 mm., for a supposed length of forearm of 1000 mm.), 
and the fifth metacarpal is practically of the same length as the 
fourth f. (2) In ferrum-equinum «a considerable shortening of the 
third metacarpal has taken place ; at the same time a much smaller 
reduction of the fourth metacarpal has occurred, so as to make 
the fifth metacarpal, slightly but decidedly, the longest of all. 
The tail is proportionately longer than in the foregoing species, 
being, on an average, in the eastern races of ferrwm-equinwm 
(nippon, tragaltus, regulus) exactly 14, in the typical form 13, 
the length of the lower leg, whereas proximas, in this point (as 
well as geographically), is intermediate between the eastern and 
western races 7. 
In all the foregoing forms, without exception, there are three 
* But there is an exact parallel in an Ethiopian species, of the affinis type, viz. 
Rh. darlingi (see the “General Remarks,” below, p. 118). 
+ It would only have made the table more complicated if I had given separate 
ciphers for all the foregoing species. The only difference (and an exceedingly small 
one) is that in simplex, megaphyllus, truncatus, nanus, celebensis, borneensis, virgo, 
and malayanus the fourth metacarpal is, almost always, a mere trifle Jonger than the 
fifth; in xereis, stheno, rouxi, thomasi, and affinis a mere trifle shorter than the 
fifth. However small this difference is, it is evidently the first faint trace of the 
modification definitely carried out in ferrwm-equinum : the fourth metacarpal always 
shorter than the fifth. 
£ It is hardly necessary to say that a short tail cannot be a primitive character in 
the order Chiroptera, taken as a whole. But, for some reason or other, we find in the 
most primitive species of the genus Rhinolophus a very short tail; in the higher 
forms of the present group we see, again, a lengthening of the tail. 
