ANATOMY OF THE LEMUROIDEA. 81 
and slight subdivision of its tendon, this conjoined muscle more closely resembles that 
in Lemur than that in Nycticebus or Loris. 
In Tarsius' it is said (no doubt by a misprint) to spring from the head and posterior 
surface of the fibula. In passing down it becomes slightly connected with the tendon 
of the flexor longus hallucis; it then splits into four separate tendons, supplying the 
four outer digits, but it takes no share in that of the hallux. 
Its tendon, again, in Professor Owen’s specimen of Cheiromys?, took no part in form- 
ing that to the hallux, but its quadruple division for the outer digits united with three 
slips coming from the flexor longus hallucis. In our specimen its condition perfectly 
resembles that described as existing in L. catta. 
FLEXOR LONGUS HALLUCIS’.—This is a considerably larger muscle than the flexor longus 
digitorum. It arises from the whole posterior surface of the fibula to its summit, and 
from the whole of the interosseous membrane, also from the peroneal side of the tibia 
towards its distal end. Its strong tendon passes in an exceedingly deep groove between 
the astragalus and the inwardly inflected tuberosity of the os calcis, and is external to 
and quite separate from the tendon of the flexor longus digitorum. In the sole of the 
foot it gives off a large tendon to the hallux, and then blends with the tendon of the 
last-mentioned muscle, forming with it the perforating tendons of the four outer digits, 
and forming the main part of those of the second, third, and fourth digits. 
Galago crassicaudatus (Pl. II. fig. 3, Pl. V. figs. 23 & 24, and Pl. VI. fig. 28, F'/.h), 
G. garnettit, and G. allenit have this muscle without any origin from the tibia; but its 
insertion is as in L. catta. 
We found Loris gracilis to agree with what we shall presently state regarding 
Nycticebus. Its tendons, however, start in common, excepting that to the hallux. It 
also concurs in forming the tendon of the fifth digit. 
In Nycticebus tardigradus* it has two heads of origin—one from the fibula, the other, 
smaller, from the tendon of the popliteus. Its insertion further agrees with L. catta; 
only in this last the slip of tendon of the flexor longus digitorum going to the hallux 
is not so strong in Wycticebus. 
In Perodicticus it is not described as a separate muscle, but as part of the flexor 
digitorum communis °. 
In Tarsius® this muscle furnishes the flexor tendon of the hallux, and is only united 
partially along the outer margin of its tendon with that of the flexor longus digitorum. 
It is said (no doubt by a misprint) to arise from the tibia, instead of from the fibula. 
In Cheiromys it is quite as in Lemur catta. 
' Loc. cit. p. 78, tab. 3. fig. 1. no, 32, and tab. 4. fig. 5. 32, and tab. 5. figs. 8 & 9. 32. 
2 Loc. cit. p. 67, pls. xxiv. & xxv. figs. 1 & 2, no. 32. Professor Owen has misprinted tibia for fibula and 
fibula for tibia in the origin of this and the following muscles. 
° Cuvier, in LZ. varius, pl. 70. fig. 3, c’. 4 P.Z.S8. 1865, p. 253, figs. 5 & 6. 
5 Loe. cit. p. 44, pl. iii. fig. 15, c. ° Loe. cit. p. 77, tab. 5. figs. 8 & 9. no. 31. 
VOL. VII.—PART I. M 
