PUFFINUS AUDUUUNI. 35 



OBSERVATIONS. 

 Variation consists of the greater or less amount of light color heneath hut this is douhtless due to age. 

 Readily distinguished from the Greater Shearwater liy the uniform sooty color. 



HABITS. 

 Tlie Sooty Shearwater.*! inhabit tlie Nortli Atlantic in suninior, coining south in ear- 

 ly autumn, often reaching Massachusett.s in Augu.^t, where they are found olflhe coast 

 in company with the two preceding species. I have seen this and the Greater Shearwii- 

 ter at sea, in June, only about fifty miles north of the Bahama.s. 



PUFFINUS AUDUBONI. 

 Audubon's Shearwater. 



PiTFixus AUDUBONI FiNtcii. V. Z. S.; 1s7l', 111. 



Plate II, 2, head of adult taken ou the Bahamas m spring. Fig. 4, young in down. 



DESCRIPTION. 

 Sp. Ch. Form, rather slender. Size, not large. Bill, rather slender, strongly curved at the tip, with 

 the nostrils not prominent. Trachea, much flattened near the mouth, but becoming gradually rounded low- 

 .er down: length to bronchial tubes, ;!.!)(). Bronchials, .JJOlong and the tymi)aniforni membranes extend their 

 entire length. Os transvcrsale. present, hut there is no semiluna membrane. Stcrno trachealis, quite well 

 developed, and there is a thin, strap-like broncho trachealis, extending from the Sth ring of the trachea to the 

 4th half ring of the bronchials. (J<]sophagus, straight, slightly dilated at the lower termination; o.oO long. 

 Provcntriculus, very large, the gh;nd surface measuring o. It ) by 1 .25; the glands arc variable in number, but 

 are much more numerous near the upjier opening, becoming fewer tow^ards the stomach, near which there 

 are scarcely any on the lower side, wiiile they are very scattering above. Stomach, very small, .G5x.55x 

 .40; walls, thin, and both they and the lining membrane are soft. Duodenum, short, 2.00, enclosing a very 

 small pancreas. Intestines, 17.("» long, and there are small, globular cuuca. Spleen, small and cylindrical. 

 Heart, ([uite large, .1.1.") .x.7n, and rather flattened. Liver, variable, but the right lobe is usually much larg- 

 •er than the left, and the gall sack is large. 







mSMMS^ 



Fic. 4, Audubon's Shearwater, Puffinus audueoxi; newly hatched downy young, one day old, tak- 

 ■en on Green Key, Bahamas, April .jth lsS4. 



