613 



B. Suckers aimiecl : gi'nera Davainea, lOchinocotyle, and 

 Ophryocoytle. 



Genus DAVAINEA R. Blanchard & Rallllet, 1891. 



{ ? ISito, Chapmania Monti<jelli.> 



Diagnosis: Worms of small or medium size. Head rounded, 

 surmounted by a rostellum or hollowed by a depression, but 

 armed in either case with a double row of numerous small 

 hooks possessing- a special form (prong and dorsal root short, 

 ventral root very long, giving them the form of a hammer). 

 Suckers rounded, bordered with several rows of small hooks 

 which are instable or persistent. Genital pores generally un- 

 ilateral but occasionally irregularly alternate; in the former 

 case (unilateral pores), the ova are generally arranged in 

 groups, in egg capsules; ovary in some species develops into 

 the uterus; eggs also isolated, scattered through the paren- 

 chyma; embryos without pyriform body. 



Type species: As the type species has evidently never been 

 proposed, I propose D. proglottina (Davaine, 1860) R. Blanchard, 

 1891, as type. 



Development: As yet little known; the larvae of some species, 

 however, have been found in certain arthropods and mollusks. 



Habitat: Intestine of birds and mammals. 



Blanchard (1891B, pp. 428-440) recognizes fourteen 

 species as belonging to this genus, and thinks that T. 

 eantaniana and T, clavulus may also be placed here. 

 Some of the forms Blanchard includes here are w<'ll 

 established, others rest upon weak character.s. 



Monticelli (1893, pp. lG-17) has recently proi)Osed a 

 new genus Chapmania which seems to be very closely 

 related to, if not identical with Davainea. His diag- 

 nosis reads as follows 



Head rounded, small, with a protractile anterior sucker 

 armed on i'ts anterior margin with a crown of very minute 

 hooklets. Suckers rather large, unarmed. Proglottids cam- 

 panulate. Genital pores unilateral. Testicle single. Ovary 

 hilnhed. dendritic. 



Monticelli took Zs.liokke's (ISSS. pp. 2 C, 41-40) 

 Taenia argentina as basis for his genus, and considered 



