ANGUS STOLIDUS, NODDY TERN. 711 



Adult, 'breeding plumage. — Both mandibles marked with more oi' lees distinct longi- 

 tudinal stria} ; their tomia inflected. Xasal sulcus deep and lonj.^, formed by the 

 rounded culmen and a prominent ridge, which runs along the upper mandible from its 

 base to beyond the nostrils, where it is gradually lost. Just above the base there is a 

 small but distinct fossa, separated by an oblique ridge from the large nasal sulcus. 

 Culmen about straight for half its length, regularly decurved toward the tip, basally 

 broad and flat. Commissure slightly decliuato-convex. Ontliue both of rami and 

 gonys concave, the former most so ; emiuentia symphysis illy defined and not acute. 

 Primaries unicolor, very broad almost to their tips, which are rounded ; first primary 

 scarcely surpassing the second. Tail very long and mnch graduated ; but there is 

 also a slight emargination, the two central r«^ctrices being a little shorter than 

 the next pair. Bill and claws black. Month black to a little beyond the angle of the 

 jaws, the fauces yellowish. Tarsi a6d toes dark reddish-brown, nearly black in the 

 dried skin. Occiput bluish-plumbeous, becoming pure white ou the front. Sides of 

 the head and neck all round with a decided wash of bluish-plumbeous. The whole 

 body is a deep fuliginous-brown, growing almost black on the remiges and rectrices, 

 with a verj' dark spot anterior to and just above the eye. 



Dimeusioun. — Length, ]6 inches; extent of wings, 31 ; wing from flexure, 10 to 10.50; 

 tail, about 6 ; bill along culmen, 1.75 ; height or width at base, 0.38 ; tarsus, 1 ; middle 

 toe and claw, 1.45 ; outer ditto, but slightly shorter ; inner ditto, 1.20 ; hallux, 0.40 ; 

 breadth of webs, 0.90 ; diameter of eye, 0.30. 



Anatomical characiers. — Mouth long and narrow, its lateral outlines slightly concave. 

 Palate nearly flat behiud ; longitudinally arched before ; soft and vascular to within an 

 inch of the tip. A prominent central ridge, beset with obtuse papilhe, bifurcated poste- 

 riorly for 0.6, to give passage to the posterior nares. The narrow well-marked lateral 

 ridges commencing one and a half inches from the tip of the bill, extending beyond the 

 termination of the median ridge, smooth anteriorly, thickly papillate posteriorly. Ou 

 each side, just within the tomia, is a groove for the reception of the inferior maxilla. 

 The palate is black nearly as far as the angle of the mouth ; the fauces yellowish. 

 Posterior nares 0.9 long, anteriorly smooth, terminally papillate. Rima glottidis 0.25. 

 The oblique converging rows of papillae on the vaulted space at the back of the palate 

 are l)ut slightly developed. Tongue 1.90 long, verj' acute, corneous for more than two- 

 thirds its length ; its posterior extremity euiargiuate, papillate. CEsophagus very long, 

 measuring, wi'.h the proventriculus, 6 inches; as usual, very muscular and distensible. 

 Proventriculus a straight continuation of the canal ; its zone of gastric follicles very 

 narrow, the glands exceedingly small. This portion of the tube does not present the 

 marked diiferences from the esophagus as regards its lining membrane that is ordi- 

 narily found. Gizzard situate very far back in the abdomen, deflected at a consider- 

 able angle toward the right ; its middle about opposite the raums of the pubis. The 

 oesophagus is not of equal calibre throughout, but dilates a good deal toward the pro- 

 ventriculus, where the muscular parietes are thicker, and the longitudinal rngie of 

 mucous membrane more numerous than elsewhere. The intestine measures 14 inches 

 in total length, from pylorus to anus. The duodenal fold is exceedingly short, being 

 le.ss than one inch. It curves round to the left beneath the gigerium. Lying below 

 the duodenal fold, and in contact with it, is the last intestinal fold, which has its apex 

 about three iuches from the origin of the cceca. The cceca are elongated, being longer 

 than in any other representative of the subfamily. They uu-asure 1.40 inches. They 

 are club-shaped, growing broader toward their extremities, after a small uniform 

 diameter for half their length. Rectum exceedingly short, barely three-qimi ters of an 

 inch. Cloaca, a.s usual, very capacious, globular, 0.75 long. The urinary and si)ermatic 

 ducts open upon well-marked elevated papilhe, side by side, and close to the posterior 

 median line. Posterior division of the cloaca well marked by elevated folds of mucous 

 membrane. The pancreas is very short, scarcely an inch in length, owing to the short- 

 ness of the duod(!nal folil. The lobes of the liver are of very unequal ilimen^ions, the 

 left being so small as to apjiear but a mere apixndage to the right. The former meas- 

 ures one and a half in length by one in breadth ; is thick, with a rounded smooth sur- 

 face. The latter is scarcely three-quarters long by one-half broad. It is of much the 

 siMue shape as the right, to which it is closely connected by a short band of glandular 

 sub.stance. The pancreatic and hepatic ducts pit-rce the intestine in clo.se proximity, 

 about two inches l)elow thti pylorus. The kidneys are one and a quarter inciies long 

 by three-iiuaiters broad. They are much less lobulated than in Slutia. and are more 

 like those of J.uriis. Their upjK'r lobes are smaUer than their lower, having very con- 

 vex holders. The lower an- sub(|na(liangnlar in shape; tlie central ones only jiartiiiliy 

 divided into .several small irregidar mas.ses. Heart elongated, tapering, acute ; its 

 width across the ba.se of the ventricles seven-touths. The trachea is short, being little 

 more than three inches ; its rings about oiu^ huiulred ; flattened above, becoming more 

 cylindrical as it proct;eds downward. Bronchi very short and ((uite wide. Tliey are 

 very feel)le ttt their eouimeucemetit, lieing almost entirely memltranons, the h.tlf-rings 

 hardly distinct enough to be counted. Tlieac number about tweuty-tbur. Muscles as 



