MUSCLES OF THE HIND LIMB. ol 
to be a peculiarity not hitherto noted, but was unmistakably present in S. 
paradoxus and may be anomalous. 
The peroneus brevis and the peroneus quinti digiti arise on the antero-external 
aspect of the fibula, the latter from the external aspect for a distance of about 
11 mm. distal from the head, and the former more internal, for a slightly greater 
distance. The tendons of both are invested in a common sheath and pass 
together posterior to the external malleolus and beneath the tendon of peroneus 
longus. Peroneus quinti digiti is inserted into the distal phalanx of digit 5, 
while the peroneus brevis passes to the ecto-proximal end of the fifth metatarsal. 
Both these tendons are simple and show no trace of secondary divisions to digit 4 
as described for Gymnura and Centetes by Dobson. Solenodon thus resembles 
Potamogale in the single attachments of these muscles. 
The extensor hallucis longus arises from the middle third of the fibula and 
adjacent interosseus ligament and passes to the distal phalanx of digit 1 on the 
dorsal side, through the same large groove on the front of the ankle, as the 
extensor longus digitorum and the tibialis anticus. 
The tibialis posticus (Plate 4, fig. 2, 7) is concealed by the flexor longus 
digitorum. It arises from the proximal end of the fibula on its posterior side 
and is more or less connected by muscular fibers with the flexor longus hallucis. 
After crossing to the ental aspect of the limb, it passes as a small tendon through 
a groove on the distal part of the tibia to the insertion into the ento-lateral 
process of the os calcis at its anterior end, not into the naviculare or scaphoid as 
commonly. Dobson states that this muscle in Solenodon cubanus retains its 
usual insertion into the naviculare, but in S. paradoxus it was found on each side, 
inserted unequivocally as above noted. 
The flexor longus digitorum, or digitorum tibialis (Plate 4, fig. 2, 1) arises 
mainly from the posterior proximal portion of the tibia. The tendon passes 
through the same groove on the ental aspect of the tibia as that of the tibialis 
posticus, and ectal to it. It becomes inserted into the ventral surface of the 
flexor longus hallucis. At the base of the carpals, it gives off a small branch to 
the rudimentary first metatarsal. This muscle in Solenodon resembles the 
corresponding one in Potamogale, rather than that of Centetes whose curious 
development has been described by Dobson. In Gymnura it is merely united 
with the next. 
The flexor longus hallucis (or digitorum fibularis) (Plate 4, fig. 2, 7) takes 
origin from nearly all but the distal portion of the posterior side of the fibula 
and adjoining middle third of the tibia. It is much larger than the flexor 
