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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 55. 



extends to spermathecal pore; a median spermathecal branch with 

 several pairs of lateral diverticula extends posteriad from near the 

 pore through about seven somites and has median ventral interseg- 

 mental pores on 19/20-24/25 or 25/26. 



Five specimens collected at Mkonumbi near Lamu, British East 

 Africa, by William Astor Chanler in 1892. 



Holotype and paratypes. — Cat. No. 16835, U.S.N.M. 



The paratype from which the drawing was made for figure 13 

 is left unsectioned. Sagittal sections were made from one-half of 

 the first 20 anterior somites of the type-specimen and similar sections 

 from a varying number of anterior somites in three paratypes. In 

 each instance the uncut half was left connected with the remainder 

 of the specimen. 



This treatment of type-specimens is not a common one among 

 students of earthworms, but seems to us to scarcel}^ need defense, 

 since it permits the careful detailed study of the internal organs 





Fig. 13.— Polytoreutus multivorus. Ventral view of 

 genital region. x5. o st p, accessory spermathecal 

 pores; g s p, modified setae and papillae; p, penis; 

 St p, spermathecal pore. 



Fig. 14.— Polytoreutus mxjltiporus. 

 Longitudinal section showing mod 

 iFiED seta (oof 19). x35. £? s, Modi- 

 fied seta; pst, diverticulum of poste- 

 rior BRANCH of spermatheca. 



which is so essential for adequate descriptions in this group of ani- 

 mals. It also avoids the disturbance and occasional loss of organs 

 which sometimes accompanies exploratorj'' dissections. 



External charaeters. — The length of the type-specimen is 14.5 cm., 

 and its maximum diameter is 0.45 cm. There are about 470 somites 

 in the type and 485 in the largest paratype of which the length ig- 

 20.5 cm. The shorter specimens have fewer somites and may not 

 be complete. The color of the specimens indicates that they were 

 pigmented on the antero-dorsal surface in life. The setae are absent 

 on five or six anterior somites and in the clitellar region. Each of 

 all or nearly all of the A^entral setae on 19-26 or 27 is surrounded 

 by a glandular papilla (fig. 13) and is modified, being nearly straight 

 (fig. 14) and of fully twice the length and nearly twice the diameter 

 of the ordinary setae which are quite small (fig. 15). Throughout 

 the greater part of the length of the worm the setal distances are 

 ftbout as indicated by the formula given above. The clitellum u 



