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ENTOMOSTRACA OF MINNESOTA. 123. 
First— As a matter of frequent observation and beyond all doubt, 
it frequently happens that a young female Cyclops becomes oviparous. 
before the moult, when it acquires its full adult complement of seg-, 
ments in the antenne and feet. Such animals are obviously larval and 
exhibit this fact in their small size, pale color, small number of eggs» 
imperfect development of serrations, spines, etc. * Schmeil himself 
has observed males in this stage with spermatophores and had before 
him a figure in my Final Report (Plate Q, 5), reprinted from the tenth 
annual report, in which this matter is plainly stated, of young gravid 
females of OC. serrulatus—a species not likely to be mistaken— with 
less than twelve joints in the antenne and two-jointed rami of the 
swimming feet. After admitting that ‘‘kein Grund vorliegt, an der 
Richtigkeit der Herrick’schen Angabe zu zweifeln,”’ he says ‘‘ Herrick 
figures, as a matter of fact, not a young form but a completely devel- 
oped animal, in which, to be sure, in certain segments of the antennze 
the normal subdivision has not taken place.’? He adds (entirely mis- 
conceiving my position as to heterogeny’: ‘‘ Dass hier nicht an einem 
Fall von Padogonie oder gar Heterogenie zu denken ist, ist selbstvers- 
tandlich.”’ Had he consulted the original paper Schmeil would have 
seen that the failure to develop a full complement of antennal joints is. 
but one of the symptoms of the larval state manifested by this speci- 
men. Moreover, such forms are found among vast numbers of adults. 
and larve in the midst of the most prolific seasons and in suitable 
situations. We claim that the next moult would have brought to this. 
very animal its normal adult structure. Nor is this an isolated case. 
Yet Schmeil could in all consistency be forced to erect a variety for 
such forms. In glaring inconsequence, we find, on p. 101, Schmeil 
says of C. clausii Heller: ‘‘Obgleich ich der Ansicht bin, dass wir es 
hier wohl kaum mit einer selbstandigen Art, sondern nur mit einer 
Jugendform einer anderen (des ©. viridis) zu thun haben,’’ ete. 
Second— As a second and entirely distinct point, though confused 
with the former by Schmeil, it is believed that many of our species, 
especially such as live in pools which undergo great changes with the 
season by reason of evaporation, intrusion of water plants or animal 
forms serving as food, etc., may, after reaching full maturity and bear- 
ing more than one generation of eggs, undergo considerable changes, 
or that, under these changed conditions, what is usually the uitimate 
condition becomes a transitory one. ‘This change may show itself not 
only in increased size but in enormous enlargement of the sete. For 
example, I have seen C. ingens with the pectinating hairs on the sete 
elongated till they became long hairs. All the spines and plates and 
serrations are exaggerated, while the relative proportions are altered. 
In the case of C. viridis this is especially liable to occur, because of 
its stagnant stations. The color changes with the rest and the change 
