Karl Pearson and Adelaide G. Davin 
365 
hibited also the two fahellae*, cyamella and lateral anterior lunula. Another 
Galago (sp. ?) gave the same result, while a series of mounted specimens provided 
sometimes (as oversights of the articulator !) the fabellae, or the cyamella and once 
a lunula. 
In Lemur macao niger, both fahellae, the cyamella and apparently hoili anterior 
lunulae were present. Nycticebus javanicus had also fabellae, cyomella and lateral 
anterior lunula ; a mounted specimen of Nycticebus tardigradus retained only the 
cyamellaf. Going further we find Loris gracilis with fahellae, cyamella and 
lateral anterior lunula, apparently but difficult to decide definitely without a 
section there was also a lateral posterior lunnla; a mounted specimen showed 
more definitely two lunulae. 
Perodicticus potto gave us fahellae, cyamella and lateral anterior lunula, and 
the cyamella was confirmed in a mounted specimen of the Calabar potto. 
We now reach cases in which we can be more or less definite as to absence of 
lumdae because the semilunars were preserved. 
Chiromys (Aye-Aye) dissected gave both fabellae and cyamella, there were no 
lumdae: see Plate XXVIII, Fig. 74a. A second specimen in the Biometric 
Laboratory was investigated with precisely the same result no lunulae. Mounted 
specimens show the fabellae as a rule ; in one we found the cyamella preserved. 
The existence of the cyamella in the Aye-Aye was, we believe, first noted by Owen. 
He makes the important point that " there is a sesamoid in the external lateral 
ligament of the knee-joint at its insertion into the head of the fibula." (See our 
Plate XXVIII, Fig. 74 b.) He also refers to the fabellae in the Aye- Aye. (" On the 
Aye-Aye." Trans. Zool. Sac. London, Vol. v. p. 53, 1866.) 
In Avahi laniger and Hapalemur griseus we found both fabellae, definitely 
no lunulae, the cyamella failed but might possibly have been removed. A mounted 
specimen of Avahi laniger as well as one of Propithecus diadema showed only 
the fabellae. In a mounted specimen of Lepidolemur microdon we found only 
cyamella and external fabella. 
Chirogaleus and Indris brevicaudata gave only the fabellae and cyamella. 
Lastly Tarsius .spectrum has both fabellae and the cyamella. Curiously enough 
as in Galago crassicaudata the mesial fabella may be larger than the lateral, 
although we have seen specimens mounted having solely the lateral fabella. We 
can only say we have not yet found lunulae in Tarsius. This is not very strong 
evidence against their existence, because the semilunars are so small that without 
fresh moist material carefully sectioned and microscopically examined it would be 
difficult to give a strong negative. When we resume our results for the Lemuroidea 
* Mesial larger than lateral. 
t Mivart and Murie {Proc. Zool. Soc. Loudon, 18(55, p. 129) in their "Anatomy of Nycticebus tardi- 
gradus" note of M. popliteus that it is inserted by a very strong tendon containing a large sesamoid 
bone. ..into the depression outside the lateral condyle. They do not mention when discussing il/. gastro- 
cnemius the existence of sesamoids therein. 
