VISCERAI. ANATOMY. 47 



color attached Ijj' delicate mesentery to the cardiac curvature of the \entral 

 portion of the stomach. Its left end curves dorsally, slightly enfolding this part 

 of the stomach, and forms a recurved lobe. When removed and spread out 

 there is seen to be a slight constriction forming another terminal lobe at its right 

 end. These lobes are not indicated by Peters in liis tlrawing of the si)Ieen of 

 S. cnbanus but otherwise the two organs apj)ear similar. 



There is a large mesenteric gland (Plate 9, fig. G) above the rectum, in the 

 dorsal mesentery, about a centimeter posterior to the left kidney. It is 13 mm. 

 long by 6.5 mm. in greatest width, with slightly lobulate border and a posterior 

 notch for the insertion of a vessel. Other smaller glands are present, 2 or 3 mm. 

 long, scattered throughout the great mesentery, particularly in the region of the 

 stomach, where close to the pylorus is a large gland aliout 5 mm. long. 



The thyroid glands (Plate 5, fig. 1 , iu'c remarkably large, situated one on 

 each side of the throat, posterior to the submaxillary glands. They are oval in 

 shape and in one specimen, measured 22 by 9.5 mm., and IS by 9 nun. respec- 

 tively. 



The thymus (Plate 9, fig. 1, /) is a large median glandular mass ]>artially 

 investing the base of the trachea vent rally just anterior to the heart. It con- 

 sists of two rounded Icjbes, one on each side, bound together by connective 

 tissue. The greatest median length of the mass is about 1 1 mm. 



In addition to these, there is a glandular mass at the axilla and another 

 just in front of the hip joint. The latter is rather large, and divided into two 

 main masses, about 21 and 15 mm. long respectively, and each about a third as 

 wide as long. These, as stated by Peters, may be lymphatic glands, or possibly 

 scent glands. They were discovered by Poey in fresh specimens of Solcnodan 

 cubanus. There are no anal glands such as are found in Gymnura. 



Fresh specimens show no skin glands. What Dr. J. A. Allen (:08, p. 513, 

 fig. S) has figured as a "glandular surface of left thigh" is apjjarently the result 

 of partial maceration of the hair follicles at tliat region. These are very large 

 and conspicuous and might readily be mistaken for the openings of glands. In 

 fresh specimens, however, there is no trace of such an area, l)ut the entire sur- 

 face is well haired. 



Mesenteries. — The great mesentery suspending the intestine from the dorsal 

 body wall is continuous for practically the entire length of the gut, and shows 

 no special modification. A short narrow mesentery connects the hver and the 

 small intestine and is continuous with a delicate membrane along the lesser 

 curvature of the stomach. 



