2008 The Zoologist— Februahy, 1870. 



terminal segments* that tlie power of flight is abrogated. The first 

 primary is always longest; the rest rapidly and regularly graduated; 

 all taper to a sufficiently fine point. The secondaries are very short, 

 and broadly rounded. The primary coverts are very long, reaching 

 much more than half-way from the carpus to the end of the first 

 primary. The first row of secondary coverts reach nearly to the end 

 of the secondaries. The under wing-coverts are ver}'^ long. The 

 axillars are short or wanting. The wing as a whole is convex above, 

 concave below, narrow, sharp, stiff, somewhat falcate. These points 

 of structure are constant throughout the family. 



The tail is very short; its length is contained, on an average, about 

 three times in the length of wing from the carpal joint. ' It is usually 

 slightly rounded, somelimes nearly square, in a few instances pointed ; 

 in a few more the central reclrices are slightly shorter than the next 

 pair. The individual feathers are usually very obtuse at the end. 

 Both sets of coverts are long ; the inferior usually reach nearly or 

 quite to the end of the tail. 



The feet are small, and placed far back, as has been said. The 

 thighs are contained within the general skin of the body. The legs 

 are feathered nearly or quite to the tibio-tarsal joint. The tarsus is 

 short, sometimes excessively abbreviated, rarely equal to ihe middle 

 toe without its claw, never (? t) longer. It is usually much com- 

 pressed, is sometimes almost as sharp as that of Colyuibus, is fre- 

 quently nearly as broad laterally as antero-posteriorly. Its covering 

 varies with different genera. It is usually reticulate behind and 

 laterally, with a row of scutellaj in front, which rareh", however, if 

 ever, extend its whole length. In some genera it is entirely reticulate ; 

 in others, the scutellation extends on one or both sides. The tarsal 

 envelope varies so much that it is not available as a character for sub- 

 divisions higher than generic. The toes are very long; the outer and 

 middle always of nearly the same length ; the inner shorter, its claw 

 just reaching the base of the middle claw. There is no hind toe. 

 Dissection reveals the rudiment of a hallux, which, however, is never 

 developed sufficiently to make even a well-marked prominence. The 

 webbing of the toes is complete. The claws are all moderately arched, 



* Cf. Mr. A. Newton's article in the 'Ibis' for October, 1862. .As there slated, 

 the humerus of Alca inipennis is of normal size ; the antibrachium, carpus and meta- 

 carpus, and their quills, are shortened. 



t Brachyrhamphus brachyptcrus is said by Braudt to have the tarsus longer than 

 the middle toe. 



