1908.] 



AYE -AYE AND OTHER LEMURS. 



701 



somewhat different. In the specimen which I dissected the I'ight 

 renal vein, which poured its contents into the postcaval headward 

 of the left renal, was formed by two trunks which, however, 

 united before entering the postcaval. This may well be a mere 

 variation. But it is worthy of note that double renal veins 

 particularly on the right side are very usual among Armadillos. 

 It is also very general in Tragulus^ . And here, again, it is on 

 the right side that the anomaly occurs. 



Text-%. 153. 



-np.y: 



Postcaval vein of CMrcmys, the right-hand figi;re of a male, the left of a female. 

 K. Kidney, o.v. Ovarian vein. r.v. Renal vein. sp.v. Spermatic vein. 



The primitive nature of this little Lemur was also shown by 

 the mode of connection of the ovarian veins with the postcaval. 

 There was no such asymmetry as has been desciibed in Ghiromys, 

 and which is so general among mammals. The veins in question 

 are opposite to each other not far from the posterior bifui'cation 

 of the single postcaval. On the left side the vein was more 

 complex than on the right side. It divided at once into three 

 vessels. This, how^ever, is not the only peculiai'ity of these veins 

 in Microcehus. From each renal vein a slender vessel ran back- 

 wards parallel with the postcaval trunk, and in the case of that 



* McClure, Anat. Anz. Bd. xxix. 1906, p. 375 ; Beddard, Am. Journ. Anat. 1907, 

 p. 112. 



