1(32 DR. B. C. A. WIVDLE .VXD MR. F. G. PVIISOXS ON^ THE [Mar. I, 



made out. In Viverm cii-etta (16) Young describes the muscle 

 as large and bilaminar, but sa3^s that the superficial part mav re- 

 present an adductor longus. Macalister says of the same animal 

 (17), that the muscle is small and normal. In two specimens ot: 

 Genet (20, 23), one of which we dissected ourselves, the pectineus 

 was single and extended halfway down the thigh ; in another (24) 

 we found it divided into an iuner and outer part. In Herpestes it 

 reaches nearly to the lower end of the femur (see fig. 2). 



In Profeles (32) and the Hya;nidae (33, 36, 37) the muscle is 

 single and unilaminar. 



In the Canidse the same arrangement exists. 



In the Ursidse Cuvier and LauriUard describe the muscle in 

 Ursus americaaus (62) as dividing into three parts, but this arrange- 

 ment has not been noticed by other observers. 



Among tbe Procyonidae we found the pectineus distinctly bi- 

 laminar in Procj/nn lotor (63). Allen (XXVI.) says of his two 

 specimens of this animal (64, 65), that the pectineus and adductor 

 brevis rise from the ilio-pectineal line and are both supplied by 

 the anterior crural nerve ; this origin and nerve-supply make us 

 regard that which he speaks of as adductor brevis as one layer 

 of the pectineus. In Nasua the condition of the muscle does 

 not seem to have been noticed, but in Cen-oUptes (72) we found it 

 distinctly bilaminar. Among the Mustelidae we have no records of 

 a bilaminar muscle. 



Adductor Mass {Adductor es femorvi). — This mass of muscles rises 

 from the ventral surface of the body and posterior ramus of the 

 pubes as well as from the ramus and tuberosity of the ischium ; 

 it is inserted into the whole length of the back of the shaft of the 

 femur. We do not feel justified in attempting to divide this mass 

 into the adductor longus, bre\is, and maguus of human anatomy ; 

 sometimes it can easily be divided in four or five layers, at others 

 it is impossible to divide it at all. 



The Semimemhranosus ri»es from the tuberosity of the ischium 

 and is often closely fused with the adductor mass in the thigh. 

 It is inserted into the internal tuberosity of the tibia, deep to 

 the internal lateral ligament of the knee, by tendon. Some of the 

 fibres are also inserted into just abo\e the internal condvle of 

 the femur and are separated from the adductor insertion by the 

 femoral artery. This pre-semimembranosus or ischio-supracon- 

 dyloideus is of special interest when compared with the same 

 muscle in other animals. In the llodents, for instance, it is often 

 quite a separate muscle rising from the caudal vertebrae ; in animals 

 as far apart as man and the kangaroos it is intimately connected 

 with the adductors, while in the macaque monkey it rises from the 

 tnberositv of the ischium and is a distinct muscle down to its inser- 

 tion. However it may vary in other respects, its insertion and 

 nerve-supply from the sciatic are always constant. In the Carni- 

 vora the ischio-supracondyloideus is always part of the semimem- 

 branosus in the thigh, and always rises with that muscle from 

 that tuberosity of the ischium, so that most writers describe the 



