1894.] ANATOMY OF ATHERURA APRICANA. 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 cords l . 



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 luug 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 lobules 2 . 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 tendinese 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 cavae and only one azygos vein. 



Reproductive System. 



The Reproductive System of the male resembles that of Hystrioc. 

 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. 

 When the prostatic urethra is opened, a very prominent verumon- 

 tanum is seen with a small utricle in the anterior part of it, about 

 g in. deep. On each side of this are two large crescentic openings, 

 the outer pair leading to the small (lower) vesiculee 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 Tocal 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 arrange- 

 ment in a specimen of the same animal. I am 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, 



