562 ANATOMY OF VERTEBRATES. 



at the broadest part : its serous coat, as in most quadrupeds, is 

 derived from both layers of the epiploon, which are reflected from 

 one margin to the stomach, and by the opposite to the dorsal 

 abdominal walls. In the Felines the spleen commonly presents 

 an elongate trihedral form,, attached to the stomach by the dupli- 

 cature extended from the angle formed by the meeting of the two 

 lesser sides. 



In the Aye-aye the spleen is an elongate, trihedral body, bent 

 at nearly a right angle upon itself, the lower portion being nearly 

 half the length of the upper one ; it is suspended in the epiploon 

 at the left and lower curve of the stomach. The spleen presents 

 a like shape and position in the Lemurs : but is less bent in 

 Lemur Mongoz. The spleen is elongate and straight in Platyrhine 

 Monkeys ; it becomes broader and thicker in Catarhines : it 

 shows a subtriangular form in the Baboon {Papio porcarius), 

 where one angle is attached to the stomach, another to the kidney, 

 and a third projects freely into the epiploon : in tailless Apes the 

 spleen more resembles in shape, attachments, and in the source of 

 its serous investment, that of Man. 



The loose nature of the suspension of the spleen somewhat 

 affects the value of the remarks on its various positions in Mam- 

 malia, given in xn. torn. iv. pi. ii. p, 617, where it is said to be 

 near the pyloric end of the stomach in a Nyctinome and a Noctilio, 

 a Phyllostome and a Megaderm among Bats, while in other 

 species of these genera it was found nearer the cardia : in a 

 Vespertilio and Rhinolophus it was observed to be bent round the 

 great curvature of the stomach. In Pteropus and Galeopithecus 

 the spleen retains its common position applied to the cardia : it is 

 relatively smaller in frugivorous than in insectivorous and sangui- 

 vorous Bats, but is generally long and narrow : it is triangular in 

 Galeopithecus. In Insectivora the spleen is loosely suspended 

 in the epiploon from the cardiac cul-de-sac ; it is relatively largest 

 in the more carnivorous of the order, e.g., the Tenrecs. 



The spleen is larger in the omnivorous and quasi-carnivorous 

 Rodents, e.g., the Rats, than in the vegetarian majority of the 

 order: it is relatively larger in Carnivora than in Ungulata. The 

 amount of hydro-carbonates to be eliminated by the liver would 

 seem to influence the capacity of the alterative receptacle of the 

 great proportion of the blood which is supplied to the bile-making 

 organ. With reference to the hypothesis of sanguifaction it may 

 be remarked that in no Mammalian order is the mass of blood so 

 great, or so full of blood-discs, as in the Cetacea ; yet in them the 

 spleen has its least relative size. 



