266 



NA TURE 



[Feb. 5, 1874 



its sides, and bending it over its body so as to be partially 

 hidden. 



" In all these operations no material was collected by the 

 animal for its nest, but only the growing e;rass was either 

 pressed down, or arranged so as to form a complete 

 retreat. 



" Unfortunately, the Frog soon disappeared altogether." 



It is very probable that other functions, as yet un- 

 noticed, may be performed by these members, since though 

 the observation just above related is the first known 

 observation of the kind, yet the manceuvie recorded is no 

 doubt a constant habit of the animal. 



Doubtless, also, the very singular actions performed by 

 the male Pi'pa and Obstetricans are performed by the 

 help of the hinder extremities. 



At the same time that the Frog shows so startling a 

 resemblance in its leg muscles to higher animals, it shows 



I 



Fig. 65.— MuscIes of Ventral Surface ot UtiiohraiicJuis. On the right 

 side, supsrficial muscles : on the left side, deeper muscles, tlie myio- 

 hyoidei, pectoralis, and external oblique being removed. Also super- 

 ficial flexor muscles of right pectoral limb of Meuobya7ichus, B, biceps ; 

 CB' and CB', coraco-brachial.s : CHE. cerato-hyoideus esternus : EO, 

 external oblique; FL, flexor longus ; CH, genio-hyoid ; MH^ and 

 MH", mylo-hyoideus ; O//, omo-hyoid ; P, P', and P', pectoralis ; 

 R^ rectus; .S", subclavlus ; 6"//, sterno-hyoid ; i'Z., supinator longus ; 

 7", triceps. 



as striking a difference from the leg muscles of animals 

 with which it is nearly allied, — namely, with those of its 



class-fellows, the Urodela. 



In Reptiles we meet with a muscle which takes origin 

 from beneath the joints of the tail, and is inserted with 

 the thigh-bone, and wliich has no certain representation 

 amongst mammals, and is called xh.^ fcitioro caudal. 



In the Urodela we also meet with ^/rinoro caiidaf, but 

 no such structure exists in the Anoura. This is not so 

 surprising when we recollect the abortive condition of the 

 tad of the Frog. It might, however, have been expected 

 that in the Tadpole, during the co-existence of the tai 

 with the hind legs, .ind while it thus extern.ally resemble 



an eft — such a muscle would transitorily e.\ist. Such, 

 however, is not the case, and the distinction is a very 

 remarkable one. 



In one point, however, the Efts resemble the Frogs, 

 namely, in the greater number and greater complexity as 

 well as the greater size of the muscles of the hind-limbs 

 than of the fore-limbs. It is well known that the Efts 



Fig. 67. — Deeper Muscles of Outer Aspect of Right Pelvic Limb of Par- 

 son's Chameleon: the ilio-peroneal cut reflected. A. adductor; B^ 

 biceps ; Z>S gluteus primus ; D-. gluteus secundus ; Z?^, gluteus ter- 

 tius ; EL. extensor longus digitorum ; F- and F^. rectus femoris ; FC. 

 femoro-caudal ; FD^. flexor longus digitorum ; FD-, flexor tertius digi- 

 torum : G, gracilis ; GE. gastrocnemius externus ; IP. ilio-peroneal ; 

 P. peroneus ; 6", tibial adductor ; SM. semi-membranosus : VM. vastus 

 ; X. gluteus maximus ; y. tendon of femoro-caudal. 



make use of their hind-limbs in attaching their eggs to the 

 leaves and branches of aquatic plants ; and further obser- 

 vations may show with regard to these animals facts as to 



Fig. 68.- -Deeper Muscles of Extensor Surface 01 Right Leg of Menopoma, 

 B. biceps ; EB. extensor brevis ; EH, extensor hallucis : ELD, exten- 

 sor longiis digitorum ; FC, femoro-caudal ; GMd and GMl. muscles like 

 the lesser glutei ; GMx and RF. great extensors of the thigh ; /, 

 muscle resembling the iliacus ; IIC, ilio-caudal ; IP. ilio-peroneal : SM 

 and ST. muscles like the semi-membranosus and semi-tendinosus respec- 

 tively: 7",^, tibialis anticus. 



the use of the members, as novel and interesting as the 

 one just cited with regard to the nest-building actions of 

 the Frog. 



St. George Mivart 



(Jo be coiitiiucfd.) 



