Letters, Extracts, Notices, ^c. 299 



wliich runs to the second digits the arrangement being as 

 shown in the accompanying figure,, which is the result of 

 some dozen drawings made both with and without the 

 camera lucida. My friend^ Dr. Stejnegei', who also examined 

 the specimen, arrived independently at the same result. 

 There is a considerable amount of connective tissue, a strong 

 vinculum in fact, about the tendons where they cross, and in 

 removing this Dr. Shufeldt and myself must have severed 

 the narrow branch connecting the f. 1. h. and the f. p. d. ii. 

 It is, of course, barely possible that this branch may some- 

 times be absent, but I do not give myself the benefit of the 

 doubt. One thing, however, I cau assert most positively; 

 I have never dissected a Humming-bird's foot in which the 

 flexor perforans digitornm did not give off three branches, to 

 digits II. III. IV. A very simple experiment will convince 

 anyone that the flex . per. dig. sends a branch to the fourth 

 digit; if the flexors of i. ii. iii. be severed, and the flexor 

 longus hallucis carefully removed, a pull on the flex. per. dig. 

 will flex the fourth digit, wliich it could not possibly do were 

 the tendons arranged as figured in the 'Dictionary of Birds.' 

 — Frederic A. Lucas. 

 Washiugton, D.C., U.S.A. 



I AM sorry for having stood godfather to a diagram which 

 has turned out to be the most incorrect and most misleading 

 of all. The gentleman to whom I felt indebted for it has 

 lost no time in informing me that it is quite wrong ; he has 

 sent me another, vouched to be correct, in which the fl. prf. 

 supplies each of the front toes with a strong tendon, while 

 the fl. h. "^goes to the 1st digit and sends slips to the 2nd, 

 3rd, and 4th ; in the case of the latter two, the slips do not 

 amount to more than a few fibres." Mr. Lucas fully agrees 

 with this statement. The little slips to digits 3 and 4 are 

 not represented in Mr. Lucas's diagram. They are, however, 

 rather important as last remnants of a regular four-split 

 condition of the tendon of the fl. h. Consequently those 

 most concerned in this discussion, namely, the Humming- 

 birds themselves, come off" best, because they prove to be 



