E. LÖNNBERG, MAMMALOGY OF ECUADOR. 75 



latter is a little shorter. These fingers sit on a level and 

 have compressed and curved claws. Tlie remaining two fin- 

 gers, which are provided with nails, sit considerably more 

 proximally, nearer the carpus, the fifth finger nearly as high 

 up as the pollex. In consequence of this the fifth finger 

 reaches only a little beyond the first phalanx of the fourth 

 finger, and the pollex, which is more slender not quite 

 so far on the second. The fingers are practically naked on 

 their upper surface and scaly, the scales being transver- 

 sely arranged as in whorls. Their palmar surface has also 

 a transverse structure by means of warts arranged in pairs, 

 which often are confluent. The palms are naked with five pads 

 and small warts between them especially near the pads (but 

 not exactly graniilar). The arrangement of these pads is 

 shown on the figure (Pl. fig. 3). The pollical pad is elon- 

 gate. Of the three digital pads the one at the base of the 

 fifth finger is semidivided. The carpal pad is much promi- 

 nent and is proximally at its base partly surrounded by a 

 thickened semilunar fold. A little further proximally follows 

 another cushion with a set of probably sensitive hairs, three of 

 which are very long so that they wben pressed down nearly 

 reach the tips of the fingers (Pl. fig. 3). This sgpracarpal 

 cushion on the posterior side of the distal end of the fore- 

 arm is sharply deflned, especially at its lower margin which 

 rises nearly vertically above the surface. It is undoubtedly 

 an important sensory organ. The inner and posterior sur- 

 faces of the forearm are nearly naked for a considerable 

 distance above the supracarpal cushion. 



In a small Marmosa I have seen twoo rather short sen- 

 sory bristles above the carpal joint in a similar situation, 

 but no cushion was developed there. A little below the 

 middle of the outer side of the forearm this Marmosa had, 

 however, a longer and stronger bristle and somewhat higher 

 up nearer the elbow a fourth still stronger and longer. 

 Sminthoj)sis crassicaudata has a supracarpal cushion or swelling 

 in the same place as Caenolestes, but only with one sensory 

 bristle. 



Although this supracarpal sensory organ is well deve- 

 loped and mnch pronounced in Caenohsies it is not charac- 

 teristic for this genus alone. Supracarpal sensory bristles 

 are also to be seen in other Marsupials as f. i. members of 



