450 MR. r. J. JACKSON ON THE ' [May 4. 



19. PoLLONEEA, Carlo. " Sjjecie nuove o mal conosciute degli 



Avion europei," Atti d. R. Accad. di Torino, 1886-7, 

 vol. xxii. pp. 290-313, tav. iii. 



20. . " Nuove contribuzioni alio studio degli Arian europei." 



Ibid. 1889, vol. xxiv. pp. 401-418, tav. ix. 



21. . Arionidte de la Region Palearctique." Boll. Mus. 



Zool. Torino, 1890, vol. v. no. 87, pp. 1-42. 



22. SiMEOTH, H. " Versuch einer Naturgescbichte der deutschen 



Nacktschnecken und ihrer europiiischen Verwandten." Zeit. 

 f. wiss. Zool. 188.5, pp. 203-366, Taf. vii.-xi. 



EXPLANATION OF PLATES XXIX.-XXXI. 



Fig. 1. The terminal ducts of the generative organs of Arion subfusaiis, 



Drap. 

 Fig. 2. The same, showing variation in the form of Uie free-oviduct. 

 Figs. 3, 4, & 5. The same, showing variations in the form of the terminal 



ducts. 

 Fig. 6. The terminal ducts of the generative organs of Arion hortcnsis, Fer. 

 Figs. 7, 8, 9, 10, 11, & 12. The same, showing variations in the form of the 



terminal ducts. 

 Fig. 13. The generative organs of ^ri'o«yMS«fs, Miill. _, 



Fig. 14. The terminal ducts of the same in natural position. 

 Fig. 15. The terminal ducts of the generative organs of Ario7i citrimcs 



Westerl. (After Bahor.) 

 Fig. 16. The generative organs of A. citriniis. (After Babor.) 

 Fig. 17. The terminal ducts of the generative organs of Arion fiiscus, var. 



boetfgcri, Poll. (After Babor.) 

 Figs. 18, 19. The terminal ducts of the generative organs of Arion caruleus, 



OUge. 



Lettering. 



alh.gl. Albumen-gland. 

 f.ov. Free-oviduct. 

 h.d. Hermaphrodite duct. 

 h.gl. Hermaphrodite gland. 

 l.v. Lower vestibule. 

 ov. Oviduct. 

 pr. Prostate. 



rd. Receptacular duct. 

 r.m. Retractor muscles. 

 r.s. Eeceptaculum seminis. 

 s.d. Sperm-duct. 

 u.v. Upper vestibule. 

 v.d. Vas deferens. 



3. Field-Notes on tlie Antelopes of the Man District,, Britisli 

 East Africa. By Frederick J. Jackson, F.Z.S. With 

 Remarks by P. L. Sclater. 



[Received February 15, 1897.] 



[Mr. Jackson, who is novr in command of ' Ravine Station ' at 

 the edge of the Mau Plateau on the main route from Mombasa 

 to Lake Victoria, has, in reply to some enquiries, kindly favoured 

 me with the subjoined field-notes on the Antelopes of the district 

 in which he is resident. — P. L. S.] 



1. BiJBALIS COKEI (Giiuth.). 



I am doing my best to ascertain the ranges of the various 

 Antelopes, but find it somewhat difficult. 1 thought I had qiute 



