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Show 1894.] ANATOMY OF ATHERURA AFRICANA. 685 to the cushion of the human larynx. The arytenoids project backward a good deal and are concave towards one another; they are attached to the side of the ring of the cricoid, facing one another, instead of at the back as in Man. The true vocal cords are therefore short, but they are well marked. There are no sacculi laryngis or false vocal cordsl. The lungs (fig. 4) are perhaps the most remarkable part of the anatomy of this animal; they are divided into a great number of distinct lobules, which are kept in position by connective tissue. Of these lobules the left lung contains 34, while the right has over 40. Five lobes can be indistinctly made out in the right lung by their more patent furrows, including the azygos lobe, which itself has five lobules2. There is no eparterial bronchus on either side. The heart is rounded at the apex. There is no definite moderator band. The musculi papillares are very long and the chordae tendineae short. The aorta has one trunk coming off from the summit of the arch, which immediately gives off the left subclavian and soon after the left carotid. As a rule the left subclavian is a separate branch in Porcupines. There are two anterior venae cavee and only one azygos vein. EEPRODUCTITE SYSTEM. The EEPRODUCTIVE SYSTEM of the male resembles that of Hystrix. Only the globus minor of the epididymis lies in the inguinal pouch, to the bottom of which it is connected by the guber-naculum. The vesiculae seminales are double on each side, the upper pair being very large and the lower quite small. The prostate is large, and the posterior part is more glandular than the anterior. W h e n the prostatic urethra is opened, a very prominent verumon-tanum is seen with a small utricle in the anterior part of it, about § in. deep. O n each side of this are two large crescentic openings, the outer pair leading to the small (lower) vesiculae seminales, the inner being the opening of the ejaculatory ducts formed by the large vesicles and the vasa deferentia. About | inch in front of the prostate is the thin-walled vascular bulb, on each side of which 1 Owen says, ' Anatomy of Vertebrates,' p. 585:-" In the Porcupines both the vocal cords and ventricles are wanting; they are mute save at the rut, when the male emits a low grunt." 2 The lobulation of the lungs of Hystrix cristata is figured by Aeby, ' Der Bronchialbaum der Saugethiere,' pi. vi. fig. 12; and I found a similar arrangement in a specimen of the same animal. I a m doubtful, however, whether it is a constant condition, because Owen, ' Anatomy of Vertebrates,' p. 577, says:- " In the Porcupine the right lung has four lobes besides the azygous lobe." Mivart describes the upper lobe of the left lung of Erethizon as being divided by two deep notches. |