4 MR. OLDFIELD THOMAS ON THE [May 3, 



Teeth of the normal insectivorous structure ; the reduction in 

 size of the incisors, two anterior upper and median lower pre- 

 molars as in Myotis, though the resemblance is clearly quite 

 stxperficial. 



Dimensions of the skull : — 



Greatest length 16 mm. ; upper length in middle line 14-4 ; basal 

 length 13*5 ; zygomatic breadth 11-8 ; intertemporal consti-iction 

 4 ; breadth of brain-case 9*6 ; palate, length 5*8, breadth inside 

 m.- 3, outside m.- 6*4 ; front of upper canine to back of m.* 6'3 ; 

 front of lower canine to back of m.^ 6 "7. 



The skeleton as a whole, including the structure of the sternum 

 and pelvis, appears to be remarkably like that of certain Vesper- 

 tilioiiidse, notably Scotophilus ; but I suppose this to be due to its 

 being of a primitive nature, without any noteworthy specialisations 

 in the way of ankyloses or hypertrophy of parts. "Wonderful 

 differences are to be found in these respects in various genera of 

 Chiroptera *, but I have not studied the subject sufficiently to 

 form an opinion as to the systema,tic value to be attached to these 

 modifications. Fortunately, Mr. Gei-iit Miller is now engaged on 

 a general revision of the classification of Bats, and is dealing fully 

 with the skeletons, so that I do not propose to do more than give 

 a short description of that of Myzopoda for incoi'poi'ation in his 

 work. 



The vertebral formula is C. 7, D. 13, L. 5, S. 4, C. 8 ; total 

 37, phis a cartilaginous rudiment of a ninth caudal vertebra. 

 None of the vertebree are ankylosed together, except of coui^se 

 those of the sacrum, thus widely difiering from the condition in 

 Natalus. Eight of the ribs are connected with the sternum by 

 costal cartilages, the ninth, tenth, and eleventh also having car- 

 tilaginous continuations not reaching to the sternum ; the twelfth 

 and thirteenth are practically without such continuations. 



The sternum is simple and little specialised ; the presternum 

 normal, with a rather elongate manubrial process (fig. 2 a), which 

 is but little expanded terminally ; the broad sterno-costal plate t 

 between the presternum and first rib, so characteristic of Bats, of 

 average dimensions ; mesosternum slender, 6 mm. in length, 

 slightly keeled, the costal cartilages of the 3rd to the 7th I'ibs 

 articulating with its sides at subequal distances, that of the 8th 

 joining it side by side with that of the 7th at its posterior end ; 

 xiphisternum 2'8 mm. long, slender, scarcely broadened terminally. 

 Proportions of scapula as sho^vn in the Plate (figs. 2 & 4), its antero- 

 internal angle produced into a well-mai'ked process projecting 

 downwards and inwards towards the vertebral column. Coracoid 

 about 3 mm. in length, therefore not long for a Bat of this size, 

 simple, slightly falciform, not expanded terminally. 



The pelvis is on the whole very similar to that of Scotophilus 



* The peculiarly antylosed vertebral column of Natalus and the highly modified 

 sternum of Kerivoiila are examples. 



f The homologies and proper name of this bone are not as yet definitelj'' settled. 

 It is the " 7 " of Winge's figure on p. 4'4 of his Chiroptera of Lagoa Santa (E Mus. 

 Lnni^ii, 1892), where its relation to the cpicoracoid of Parker is discussed. 



