BRAIN OF FUR SEAL. 21 



The mammary glands are two iu number. Each is loug and triangular, reaching 

 from the fore limb to the posterior end of the body. The two are divergent in front, 

 but posteriorly are closely approximated but not united. Each is provided with two 

 very small abdominal teats. Iu a very old cow the mammary glands become absorbed 

 and mostly replaced by fat. 



THE URINARY ORGANS. 



The kidneys are oval, with the inner border slightly concave, and are a little 

 flattened dorso-ventrally. In a bull they are about 4.75 inches loug. The hilus is 

 small. The pelvis of each divides ultimately iuto a large number of small tubules, 

 ending each in a calyx. The papilkc opening into these calices have no regular 

 arrangement, since they are turned in all directions either toward or away from the 

 hilus. The urinary Madder is small, about 2.5 inches in a bull, and is pear-shaped. 

 The nracliis is large and remains so throughout life. 



THE BRAIN OF THE FUR SEAL, CALLORHINUS URSINUS; 



WITH A COMPARATIVE DESCRIPTION OF THOSE OF ZALOPHUS CALIFORNIANUS, PHOCA 

 VITULINA, URSUS AMERICANUS, AND MONACHUS TROPICALIS. 



By Pierre A. Fish, D. Sc, D. V. S., 

 New Yorlc State Veterinary College, Ithaca, N. Y. 



INTRODUCTION. 



The specimen was from a young male pup 25 inches in length, weighing about 12 

 pounds. The brain was still incased in the dura, and on the basal surface portions of 

 the cranial bones were left adherent to this membrane. An occasional cut through 

 the dura caused a protrusion or hernia of the cerebral substance. 



The weight of the brain in the fresh condition, as reported by Mr. Lucas, was 10 

 ounces and 240 grains. This included the dura with the attached cranial fragments. 



The specimen was ijreserved in a "rather strong solution of formalin," and, except 

 for some swelling of the tissue and softening of the interior, was in a very good condi- 

 tion. The bloating was indicated by the increased weight, which, immediately after 

 the receipt of the specimen, December 12, was found to be 13 ounces, a gain of about 

 3 ounces ; the closure of the fissures and the cerebral hernias. The weight without 

 dura and attached fragments of cranial bones after preservation from September 1 to 

 December 12 was 9^ ounces and 80 grains (avoirdupois). The lateral girth was 26 

 centimeters. The longitudinal girth with the oblongata cut off at an even level with 

 the caudal surface of the cerebellum was 24 centimeters, being slightly less than the 

 former. This may, perhaps, be accounted for to some extent by the tape resting 

 slightly in the intercerebral cleft, and to the bloating, as this would affect the lateral 

 rather than the longitudinal circumference. 



The brain, as indicated by the girth measurements, was of a subglobular form, 

 slightly tapering at the ends, and its outer substance, though firm, was not unyielding. 

 Twenty-four hours' immersion in 95 per cent alcohol served to contract the nervous 

 tissue sufficiently to open the fissures, and yet to retain enough flexibility of their 



