LERNEAlUE. 
321 
That part of the history of the Lerneadse which is 
connected with their sexual relations and propagation is 
still involved in much obscurity. But the details we have 
received from Nordmann and Kroyer, with regard to the 
males, are no less singular than many of the other curious 
parts of the history of these animals. By some of the 
earlier observers it was supposed that those individuals 
which had not oviferous tubes were males, while others 
imagined that they were hermaphrodites. Neither of 
these opinions, however, will stand the test of inquiry. 
The ovaries of the female, after the eggs have attained 
maturity, burst and disappear, and thus, as Kroyer ob- 
serves, “ the Lernea which to-day was considered a female, 
to-morrow might be regarded as a male.” In the course 
of investigating different species of Lerneadse, Nordmann 
discovered, in several instances, small bodies adhering to 
the generative organs of the females, which, on closer im 
spection, proved to be animals that differed very much in 
appearance from the female, and, on the contrary, bore 
considerable resemblance to the young ones in the first 
stage of their development. These he believed were the 
males, and though Burmeister has thrown great doubts 
as to the entire accuracv of Nordmann ’s observations, 
his statements as to the fact of these animals being males 
are borne out by Kroyer and others. It is probable, as 
Nordmann remarks, “that the males and females are 
mixed together when they come out of the eggs, but that 
they develope themselves differently at the last change of 
skin.” They continue to show uniformity in regard to 
the form of the head, and the form and situation of the 
parts connected with it, but they want the apparatus for 
attaching themselves which the females possess, having 
instead, two pairs of strong, hooked feet. They differ 
constantly in the form of the other parts of the body, and 
show a remarkable diversity from the female with respect 
to size, being very much smaller. These males bear a 
strong resemblance to each other, even in different genera, 
in which the females are very unlike. This fact and the 
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