77 
for a lacking sucker, and, as mentioned above, it is widened at the 
hinder end of the body. Furthermore, in the latter species the 
pharynx begins immediately behind the brain, a striking feature 
for an Acotylean Polyclad. I regard this as a veritable dislocation 
of benefit for the collection of food. The small size of the pharynx 
is another remarkable feature. With the knowledge of the common 
type of a large folded pharynx in the Acotylea, one is entitled to 
speak of a direct reduction, when it here has a very small 
dimension. Through its stay with Pagurids, the problem of acqui- 
ring food has been solved in an expedient way and thus brought 
simplification of the prehensile organ. A striking contrast to the 
reduced pharynx is the gigantic development of the intestinal system. 
Inside the muscle wall and nerve net, the body is nearly completely 
filled up with stout intestinal canals, producing the strengest im- 
pression of its working capacity. The intestine demonstrates clearly 
the excellent nutritive State of the animals; I cannot remember 
having seen such enormous development of the intestine in any 
other Acotylean Polyclad. 
The genital system of my specimens of Emprosthopharynx 
opisthoporus also affords a noteworthy feature. Taking into consi- 
deration the sizes and the complete copulatory organs of the speci¬ 
mens, one is rather astonished to observe the undeveloped State 
of the gonads. The ovaries are so young that it is really a very 
difficult task to recognize them among masses of young stages of 
glandular cells. Though the seminal canals, as well as the vesicula 
seminalis, carry sperma, the testes are extremely small, having on 
the sections usually only 10—20 cells. These conditions may have 
the sinTple explanation that the collection of the specimens were 
made before the season of reproduction of this species had set in, 
as all the specimens agree in having extremely undeveloped ovaries. 
It is, however, not impossible that this condition bears upon the 
circumstance that the specimens leave the host at a comparatively 
early time for the purpose of carrying out the reproduction. I 
admit readily that the facts are not at all conclusive, and I would 
not have made the hint if I had not seen my Gilbertean species 
jOf the same genus. It presents, in spite of its minuteness, the 
most striking contrast in regard to the gonads to E. opisthoporus. 
The gonads seem there to have actually supplanted the intestine. 
