394 
POPULAE SCIENCE EEVIEW. 
prolongation of the latissimus dorsi to the olecranon, a thoracic rectus, and 
many others. In several species of monkey examined by me, peculiarities 
were observed which have not been before recorded ; such as a fourfold 
series of pectoral muscles, the fusion of gluteus medius and pyriformis, the 
existence of a coraco-capsular muscle, as well as of the hitherto unnoticed 
muscle infra-spinatus secundus, &c. These all occurred in the Capuchin 
monkey ( Cebus capucicus). The opponens pollicis was present in this cebus, 
and also in a cercopithecus quite separated from the other short muscles of 
the thumb. An extensor of the metatarsal bone of the great toe was like- 
wise present in several species, either with or without a separate extensor 
hallucis. An accessory scalenus likewise occurred in cebus, as well as a 
double gemellus inferior. In no instance was the slip peroneus quartus 
present, which is of such frequent occurrence in man, but peroneus quintus 
existed in many species. Many of the above arrangements have been found 
as anomalies in the human subject. 
