466 Mr Appleton, The Gluteal Region of Tarsius spectrum 



The Gluteal Region of Tarsius spectrum. By A. B. Appleton. 



[Plate IV.] 

 [Read 16 May 1921.] 



Attention will be here called to certain anatomical features 

 which have come to light in the course of a special examination of 

 the thigh musculature of Tarsius, an animal interesting not only 

 for its peculiar saltatory method of locomotion in the trees, but 

 also for the varied Primate features exhibited in its anatomy. It 

 combines features of the Insectivora, of Lemuroidea and of Anthro- 

 poidea, and it is in comparison vnth. these animals that its muscu- 

 lature must be chiefly considered. 



The dissections on which the follomng account is based were 

 made upon two Tarsii kindly provided by Dr W. L. H. Duckworth*. 



Burmeister's classical description of 1846 provides a careful and 

 accurate description, but he had not the advantage of that masterly 

 study by Lechef in 1883 of the pelvic region of Insectivora for 

 help in a determination of the identity of the various muscles 

 found in Tarsius. 



Attention in this paper will be centred on two muscles which 

 are absent in some Primates and in many other Mammalia; but 

 which are not uncommonly found in the more primitive of living 

 Mammalia. These muscles are the femorococcygeus and the caudo- 

 femoralis — employing Leche's nomenclature. They apparently have 

 their counterparts among Monotremes (Leche) and the latter 

 among Keptiliat. 



The superficial gluteal musculature of Tarsius consists of a 

 thin sheet attached to the 3rd trochanter of the femur, and a thicker 

 band passing from the caudal vertebrae to the back and outer 

 margin of the femur. 



The latter of these we here describe as the femorococcygeus 

 muscle. 



The thin muscle sheet attached to the 3rd trochanter, which, 

 with Burmeister, we regard as the conjoined tensor fasciae latae 

 and superficial gluteus, arises from the crest of the ilium, and, 

 through the lumbodorsal aponeurosis, from sacral spines, extend- 

 ing as far back as the 1st caudal vertebra. 



* References are made to dissections of specimens of Tupnia, Lemur, Simia and 

 Troglodytes, also so provided. 



t Leche, K. Svensk. Vet. Akad. Handl. 1883. 

 % Caudifemoralis of Gadow, Morph. JaJirb. 1882. 



