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mash their skull, leaving them for dead, you may come in an hour after, 
and they will be gone quite away.” 
This gemmiparous theory of Lawson that the “female doubtless breeds 
her young at her teats,” illustrates the superficial nature of the first 
observations on Marsupial reproduction. 
Early authors—among them Pennant—contended that “the pouch 
was the matrix of the young Opossum, and that the mamme are, with 
regard to the young, what stalks are to the fruit.” 
De Blainville speaks of two sorts of gestation, one uterine, the other 
mammary. | 
In 1819 Geoffrey St. Hillaire inquired of naturalists: “Are the pouched 
anima’s born attached to the teats of the mothers?” 
Gcedman, in 1826, admits, in his otherwise complete history of ie an- 
imal, that ‘‘the peculiarities of 2ts sexual intercourse, gestation, and par- 
turition, are to this day involved in profound obscurity.” 
DeKay, in 1842, states: “The young are found in the external abdom- 
inal sac, firmly attached to a teat in the form of a small gelatinous body 
not weighing more than a grain.” 
This was nine years after Owens’ observations on the development 
of the Great Kangaroo. DeKay, however, simply quoted such natural 
history literature as was nearest to hand; and, as is remarked in the 
Biblicgraphy of North American Mammals (Gill & Cowes), DeKay’s 
Fauna of New York ‘has not been recognized as of high authority, nor 
has it exercised much influence upon the progress of science.” 
It was long believed that there existed a direct passage from the uterus 
to the teat, but this, of course, was disproved by dissection. Another 
Opinion was that the embryo was formed where first found. 
It is at once seen that the tacts regarding the reproduction of this 
common animal have been developed very slowly, and not until Owen 
gave an exact description of the corresponding organs in the Kangaroo 
and discovered the foetus en utero, could naturalists conclude the discus- 
sion of reproduction in the Opossum. 
Audubon and Bachman attempted for several years to secure gravid 
females, but were baffled, as also were various French and English nat- 
uralists, by the fact that the Opossum does not breed in confinement. 
Another difficulty was that the females retire to their burrows during 
the period of utero-gestation, which, in North Carolina, the seat of 
Audubon’s observations, is about the last of February and first week 
of March Of thirty-five taken at that time (1847), in three successive 
nights, there was not a single female; but a week later, when the young 
were in the pouches, more females were taken than males. In February, 
