324 



PEOF. F. Q. PARSONS ON THE 



Muscles of the Posterior Extremity. 



Sartorius and Tensor fascice femoris. — These two muscles are 

 feebly developed even for a rodent. 



Ecto-gluteus and Caudo-femoralis (Agitator caudse). — When I 

 described the muscles of the Sciuromorphine and Hystricomor- 

 phine Rodents in 1894, I had not learned to draw any distinction 

 between these two. The fact, however, was recorded tbat " in 

 Sciurus, Spermopliilus, and Pteromys the gluteus maximus (ecto- 

 gluteus) is inserted by two slips, one into tbe third trochanter, 



Fig. 3. 



Muscles of Thigh (outer side). 



S.T., Semitendinosus ; G.M., Ectogluteus ; A.C., Caudo-femoralis (Agitator 



caudse) ; Bi., Flexor cruris lateralis (Biceps). 



the other into the lower part of the femur." I have now no doubt 

 that the upper of these is the true ecto-gluteus, the lower the 

 caudo-femoralis or agitator caudse. Anomalurus resembles these 

 animals in the low insertion of the latter muscle ; indeed the ecto- 

 gluteus and caudo-femoralis together are inserted into the whole 

 length of the femur (see fig. 4.) 



The Meso-gluteus, JEnto-gluteus and Gluteus ventralis (8canso- 

 Tins') were present ; the latter I have not hiterto seen in sciuro- 



