20 SOLENODON PARADOXUS. 



of the expanded cartilaginous end of the xiphisternuni. The fibers converge as 

 they pass obhquely forward to the insertion, 16 mm. in length, along the antero- 

 median edge of the middle third of the humerus. The clavicular portion of this 

 muscle (Plate 6, fig. 4, c) originates from the ecto-posterior border of the clavicle 

 and is more or less confluent distally with the main mass of the cctopectoralis, 

 though practically distinct to the common insertion. 



The entopedoralis (Plate 5, fig. 4,/) arises just underneath the cctopectoralis, 

 from the antero-ventral margin of the second rib, posteriorly to the base of the 

 last sternal rib as a thin flat sheet, that becomes thicker as its fibers converge 

 anteriorly to a tendinous insertion 4 mm. long at the head of the humerus, on its 

 median face, just ental to the bicipital groove. At about the insertion of the 

 fifth rib, there is a slight division of this muscular sheet so that its origin may be 

 said to consist of an anterior and a posterior i)ortion. These two parts evidently 

 correspond to the two divisions described in Centetes by Dobson, although in 

 that genus they are somewhat more extensive and distinct. 



The subdavms (Plate 5, fig. 4, d) is a very narrow band of muscle arising 

 from a tendon on the anterior side of the first rib, at about 2 mm. dorsal to the 

 sternum. It passes antero-dorsally to a tendinous insertion on the ental aspect 

 of the clavicle just proximal to its articulation with the acromion. This muscle 

 is about 30 mm. long and 2 mm. or less in width. In Centetes, according to 

 Dobson, it is not present, but in Gymnura is developed about as in Solenodon. 



About 3 mm. dorsal to the origin of subscapularis, is the large tendinous 

 insertion of scalenus secundus or anticus. It arises from the transverse processes 

 of all the cervical vertebrae except the atlas, by tendinous and muscular fibers. 



Scalenus 'primus arises dorsally to the last, from the transverse processes of 

 the 3d, 4th, and 5th cervicals and is inserted on the thorax as far back as the 

 fourth rib, in close juxtaposition to the ventral border of serratus magnus. 

 The brachial plexus takes exit between the two scaleni. 



The scalenus muscles appear thus to be much like those of Centetes and 

 Potamogale, and differ from those of Gynunn-a and Erinaceus in that the anticus 

 is present, whereas in the last two, according to Dobson, it is absent. 



