Karl Pearson and Adelaide G. Davin 
803 
(New World Monkey). In Gijnoceplialus he found sometimes the mesial sometimes 
the lateral the larger. In the remainder the lateral was invariably the largei'. 
Neither Meckel nor Gruber* refers to the cyamella as existing in either Simiadae 
or Cebidae. 
Keith in the above-mentioned thesis takes Hemnopithecus as his type. He 
thus describes the relation of the muscles in his type to the sesamoids : 
Gastrocnemius. Origin. External liead ; arises by musculo-tendinous fibres 
from a sesamoid embedded in the general capsule of the knee-joint and plying 
over the upper convexity of the external femoral condyle, and from the shaft 
of the femur immediately above and external to the femoral condyle (p. 296). 
Internal Head : from a sesamoid situated similarly to that of the external 
head and from the shaft of the femur immediately above the internal condyle. 
Plantaris. Origin ; from the sesamoid in the external head of gastrocnemius 
(p. 304). 
Popliteus. Origin. By a rounded tendon from the lateral aspect of the external 
femoral condyle beneath the external lateral ligament and within the capsule 
of the knee-joint.... There is a sesamoid in the tendon over the external tibial 
tuberosity (p. 307). 
The arrangement of the muscles relative to the sesamoids in Semnopithecus as 
given by Keith is curiously like what we have learnt of the relation of the 
muscles to the fabellae and cyamella when they occur in man. This is peculiarly 
true of 'plantaris, and is evidence, similar to that provided in the memoir on the 
Femur by Pearson and Bell, that in a number of respects man is closer to the 
Simiadae than to the Anthropoidea whether by retaining more primitive characters, 
or by reverting to earlier types as better suiting his differentiated development. 
The cyamella as well as both fabellae are present not only in Semnopithecidae, 
but in macaques, Cynocephali and practically all the Simiadae, we have been able 
to investigate f. Our drawing (Plate XXVII, Figs. 71 a and 71 b) shows the two 
fabellae and the cyamella in Mycetis palliatus, both in position and after extraction. 
Lastly we note that we have not been able to find lunulae in any knee-joint we 
have examined of the Simiadae. Should they occur, we believe their appearance 
is very rare. 
Cebidae (New World Monkeys). Here the problem is somewhat easier than 
in the Simiadae. The bulk of the species being smaller in size our purchased 
specimens were less " clean," i.e. the muscular attachments remained. We were 
thus better able to give positive evidence as to the non-existence of lunulae. 
(i) We found both fabellae in Hapale aurita (white-earecf marmoset), Midas 
oedipus, M. midas, M. ursulus (two specimens), M. auritus (golden marmoset), 
* It is the more noteworthy in Gruber's case for he does refer to a large cyamella in Stenops 
tardigradus. 
f We have rioted cyamella in Nasalis larvatus, in Macacus (the Bonnet monkej), it/, inuus, etc. and 
believe that it is general in the Simiadae, although usually cleaned oS in mounted specimens. 
