ABYSSINIAN HOMORUS. 131 



necessary for the classification of these forms remain still 

 to be investigated. 



Homorus pfeifferi of Kobelt's monograph, p. 90, is an 

 Achatina; see p. 24 of this volume. 

 The species are arranged thus : 

 Abyssinian species 



Typical group, species 1, 2. 

 Group of H. darnaudi, species 3 to 10. 

 Subgenus Subulona Martens 



Species of the Lake region and East Africa, 11 to 20. 

 West African species, 21 to 34. 



Abyssinian Species. 



(Typical Group.) 



1. H. CYANCSTOMA ('Ruppell' Pfr.). PL 58, figs. 40, 41, 42. 



- Shell turrited, the apex obtuse ; buff variegated with longi- 

 tudinal brown streaks. Whorls 9 to 10, rather flat, the last 

 slightly exceeding one-third the length of the shell. Colu- 

 mella arcuate, obliquely truncate. Aperture oblong-oval, 

 milk-white inside; peristome simple, blue-margined. Length 

 48, diam. 15 mm. ; aperture 18 mm. long, 8.5 wide in the 

 middle (Pfr.). 



Northeast Africa: Abyssinia (Ruppel). 



Achatina cyanostoma Riippell Mss., PFR., Symbols ii, p. 

 58 ; Conch. Cab. p. 336, pi. 29, f . 8, 9 ; Monogr. ii, p. 259 ; iii, 

 498 ; iv, 608 ; vi, 228 ; viii. 282. REEVE, C. Icon, v, pi. 13, f. 

 44. MARTENS, Malak. Bl. 1865, p. 182, 200; 1866, p. 95. 

 MORELET, Voy. Welwits'ch, p. 40. Homorus c., ALBERS, Die 

 Hel. 1850, p. 196; edit. 2, p. 200. KOBELT, C. Cab. p. 88, pi. 

 24, f . 1. POLLONERA, Bull. Soc. Mai. Ital., xiii, 1888, p. 73. 

 Subulina cyanostoma BECK, Index p. 76. JICKELI, Moll. Nord- 

 Ost-Afr. p. 147, pi. 2, f. 7 (dentition). BGT., Malac. Abyss, 

 p. 120. Glandina cyanostoma PHILIPPI, Abbild. i, p. 134, 

 pi. 1, f. 4. 



The apex is rather large, rounded, the first whorl a trifle 

 sunken at the tip, rapidly increasing, the next whorl or two 



