114 A. A. W. HUBRECHT., 
simplified process in which the trophoblastic activity had 
considerably subsided—we would then have no difficulty in 
understanding that similar simplification and change of 
function, leading to parallel results, had occurred in other 
orders of mammals. As such we may count certain Hdentata 
(Manis) and the Lemurs, although our actual acquaintance 
with the former is yet very scanty. 
We know that in Myrmecophaga and Dasypus there is a 
discoid micrallantoidean placenta, that in Orycteropus 
capensis the placenta is zonary (as yet very imperfectly 
known), that in the sloths it has amore cotyledonary character, 
whereas in Manis more recent investigations (also extended 
to histological detail) of Max Weber (91) have made us ac- 
quainted with a placentation very much like that of the simph- 
fied Ungulates, but at the same time with very marked ves- 
tiges of trophoblastic proliferation (Fig. 155). Considerable 
maternal proliferation of the uterine mucosa, such as was also 
figured for Manis by Weber, suggests the probability of 
descent with simplification from ancestors with more com- 
plicated arrangements. But the delicate question whether 
this latter proliferation is, indeed, maternal or—as has been 
proved in similar cases in other orders—trophoblastic will 
first have to be solved. 
At all events, for the Hdentata more extended researches 
on all the living genera should elucidate the question whether 
simplification in the direction of aso-called diffuse placenta is 
the real explanation of many of the facts here encountered. 
It should be borne in mind that any direct comparison of 
Dasypus on one hand and Manis on the other may be as mis- 
leading as that between Lemurs and Primates, because also 
on paleontological grounds the old order of Kdentata is being 
split up into two or three independent ones, comprising, one, 
the Nomarthra (by Max Weber [’04] again sub-divided into 
the separate orders of Pholidota and Tubulidentata), the 
other the Xenarthra. 
And now, in the third place, the Lemurs. Their so-called 
diffuse placenta, of which I gave figures fourteen years ago 
