10 A Review of the Muscles used 
highly interesting, to say nothing of its importance, to look 
up the subject for other groups of birds. Its importance at 
once becomes evident by finding it in such a form as Am- 
pelis, showing by this character, at least, the passerine af- 
finities of this bird over its clamatorial ones, which latter 
have been more than once suspected, at different times, as 
predominating in its organization. 
4. The bicipital slip to the patagiwm, (figs. 5 and 6 B. 
slip). This is a fleshy fasciculus of muscle that is differen- 
tiated off from the anterior surface of the biceps, and pass- 
ing between the cutaneous folds of the patagium becomes 
inserted into the tendon of the tensor patagit longus at 
about the middle of its course. 
Garrod states that ‘‘ the presence or absence of this muscu- 
lar fasciculus is a very constant character among closely 
allied birds.” He not only found it in the Caprimulgi, but 
also in Plovers, Cranes, Gulls, Auks and some few other 
groups. In figure 6, I present its appearance as it occurs 
in our Mourning Dove, a bird I especially dissected to show 
it as an illustration in the present connection. 
Professor T. Jeffery Parker describes this muscle for the 
Common Pigeon (Zootomy p. 251) as the tensor patagii ac- 
cessorius, and says “‘its anterior border is connected by 
fascia with the tendon of the tensor longus, and from its 
posterior border a long stout tendon is given off which 
passes outwards, soon becoming parallel to the tendon of 
the tensor longus, and having a common insertion with 
Mie 
If this last tendon be present in our wild pigeons, it is 
very feebly developed and consequently easily overlooked. 
I did not detect it in the Dove above alluded to, and must 
believe it was absent in that particular specimen. Where- 
ever [ examined it, it has invariably agreed with Garrod’s 
description of it. 
5. The expansor secundariorum (Fig. 5, Exp. Sec. ), 
although of insignificant size, is a muscle that has proved 
of no little value as a classificatory one. Garrod spoke of 
it as the Ciconine character, as it was so well developed in 
