Vol. XXviii] ENTOMOLOGICAL NEWS. 355 



v.'astes of the ponds. Nymphs appear early, and have only 

 four molts, a fact repeatedly tested under varying conditions. 

 This is specially noteworthy, as the general rule in the Heterop- 

 tera thus far observed is five molts, exceeded when there is 

 variation and equaled in the single instance known to me, of 

 Riptortus linearis, one of the Alydids of India, as recorded by 

 Kirkaldy and Kershaw.^ 



When the species was first bred in 1904 I thought there 

 was some error in counting the molts. It was again raised in 

 1905, with the same result. Finally, in 1908, it was once more 

 bred under carefully controlled conditions ; a batch of ova was 

 separated in a small aquarium, and as each nymph emerged 

 it was separated in a small Stender dish. A careful record of 

 the dates of molting was kept on its ground glass cover as well, 

 as in my note book. My previous results were fully confirmed. 



The complete transformations in my aquaria took place in 

 varying periods of from 22 to 59 days for the full cycle from 

 oviposition to adult, or from 14 to 49 days for the nymphal 

 instars. However, the majority run between 14 and 18 days 

 for the nymphal instars, or somewhere between 22 and 25 days 

 for the period from oviposition to maturity. Neither the sex 

 nor the period of the summer seems to make any difiference 

 in the developmental period. In midsummer the molts are 

 between 3 and 5 days apart, the maximum for any one molt 

 being 1 1 days and minimum 2, but no one instar seems to take 

 longer than any of the others per se. During the summer, 

 broods overlap, as oviposition is continuous, and taking four 

 weeks as an average, it makes possible say five to six genera- 

 tions in a season, from early May to late September. 



As the days grow colder in late summer and early fall the^'- 

 begin to grow less in number, and finally they disappear for 

 the winter. However, under favorable climatic conditions, this 

 species may breed throughout the year. A few were kept in 

 an aquarium through one winter. It was near a window, and 

 the room being in a steam-heated apartment was warm. They 



2 1908 J. C. Kershaw and G. W. Kirkaldy, Tr. Ent. Soc. Lond., pp. 

 59-62 "On the Metamorphosis of Two Heteropterous Hemiptera from 

 Southern China," pis. iv and v. 



