559 



fuiuish the data wliich are demanded in science ol lo 

 day, althougli it shows uliat tlie pr()l)al)le life history 

 is. 



Davainea tetraguna of chickens.— Plana (1881, 1882) found two 

 larvae (PI. XVIII, figs. 228-229) in snails of the genus Helix, 

 which he associated with this chiclten tapeworm (PI. XVII, 

 ligs. 219-227, PI. XVIII, figs. 231-235). 



Dicranotaenia coronula of ducks. ^Mrazek (1890) found larvae 

 (PI. Ill, fig. 25) in fresh-water mussel crabs (Cypris ovum and 

 Cypria ophthalmica (Cypris compressa); Rosseter (1890) found 

 a cysticercoid in Cypris cinerea, and Moniez (1891) in Cypria 

 ophthalmica and Candona Candida, which the three respective 

 authors have associated with D. coronula of ducks. 



Dicranotaenia spenoides of chickens — Grass! & Rovelli (1889A, 

 1892) claim to have found cysticercoids (PI. IV, fig. 40.) in earth- 

 worms (Aallobophara Foetida) which they associate with this 

 species of tapeworm (PI. IV, Figs. 37-38). 



Drepanidotaenia fasciata of geese.— Mrazek (1890, 1891) classi- 

 fied a cysticercoid (PI. VI, figs. 67-70) found in fresh-water 

 crustaceans (PI. VI, fig. 67) (Cyclops agllis) as the larva of this 

 cestode (PI. V, figs. 56-66). 



Drepanidotaenia gracialis, of ducks and geese. — Cysticercoids 

 (PI. VIII, Figs. 94-99) found in fresh-water mussel crabs (Can- 

 dona rostrata by Scott, 1891, p. 314; Cypris cobpressa by Mrazek, 

 1891; Cyclops viridis by Mrazek, 1891, and Cypria ophthalmica 

 by Moniez, 1891, p. 26) and in copepods (Cyclops sp. ?) by 

 Schmidt, 1894, are looked upon as the larval stage of this para- 

 site (PI. VII, 80-85). 



Drepanidotaenia infundibuliformis of chickens and ducks. — 

 Grassi & Rovelli (1SS9A, p. 104; 1892) state that the larva (PI. 

 XV, fig. 191) of this parasite (PI. XIV, figs. 173, 178) is found in 

 the house fly. 



Drepanidotaenia setigera (PI. XIII. fig. 154) of geese. — Infec- 

 tion attributed by von Linstow (1S92B, p. 503), to a cysticercoid 

 found by Schmril in copepods (Cyclops brevicaudatus). 



Drepanidotaenia sinuosa (PI. X, fig. 118) of ducks and geese. — 

 Supposed to develop from cysticercoids (PI. XI, figs. 130, 1.35) 

 found in flea crabs (Gammarus pulex) by Hamann (1889, pp. 

 1-7; in copepods (Cyclops \'iridis. C. agilis, and C. lucidulns) by 

 Mrazek. 



Drepanidotaenia tenuirostris of geese. — Supposed larval stage 

 (PI. XIV. figs. 16.^.. 168) was found in flea crabs (Gammarus 



