264 
Amoehotaenia i^plienoides 
The nomenclature has undergone many changes. The species was 
first called Taenia cuneata by von Linstow. Railliet altered it in 
successive years to Taenia sphenoides, Dicranotaenia cuneata, and D. 
sjdienoides. In 1899 Cohn created a new genus, Amoebotaenia, for it, 
making it the type species and calling it A. sphenoides, a name which 
he afterwards changed to A. cuneata. Under this name it was cata¬ 
logued by Fuhrmann ; Ransom finally altered the name to A. sphenoides, 
the specific name “ cuneata ” having already been preoccupied. 
In common with most bird Cestodes, nothing is certainly known of the 
life-history. Grassi and Rovelli (1892) found in the brandling (Allolobo- 
p)hora foetida Risen) cysticercoids which they beheved to be the young 
stage of A. sphenoides, an assumption based upon comparisons of the 
hooks of the two forms, and upon the fact that the cysticercoids could 
not possibly be the larval stage of any of the other tapeworms found in 
the vicinity. No feeding experiments were made however, so that the 
assumption still remains unproved. 
External Characters. 
The wedge-shaped form described by various investigators is very 
characteristic of this species, and affords a convenient method of identi¬ 
fying it roughly from other tapeworms. This only apphes to young and 
mature forms however ; as the cestode becomes older, the more posterior 
proglottides cease to increase more rapidly than the preceding ones, 
so that the greatest diameter of the strobilus is at about the posterior 
c|uarter of the worm; after that the worm begins to taper off again 
(PI. XX, fig. 1). The number of proglottides varies according to the age 
and completeness of the specimen. Magelhaes and von Linstow found 13 
the maximum, while Cohn’s specimens had 19 and 24 : I have often had 
one with 20 and once one with 23. 
In shape each jaroglottis is like a very much trmicated pyramid with 
an elongated rectangular base, the smaller end being directed anteriorly. 
Seen horizontally, it is much wider than long, and both anterior and 
posterior margins are slightly curved posteriorly. A longitudinal 
vertical section is rectangular with a small semicircular projection 
anteriorly and a corresponding semicircular depression posteriorly 
(PI. XXI, fig. 10). The groove this depression causes runs from side to 
side of the proglottis, but gradually vanishes towards each lateral 
margin so that the extreme end sections of a proglottis show no signs 
of it. The rounded anterior extremity of each proglottis fits into the 
