224 



adapted to her purposes. Frequently as many as ten eggs will be found 

 under a single scale. When this is the case, the eggs adhere to one 

 another somewhat and are often irregularly placed, as if two or three 

 insects had in succession oviposited in the same place. 



Whereas the Blattidcv show the greatest fixity in habits of oviposition 

 of any of the Orthopteran families, the Locustidce exhibit the greatest 

 variety. Some species like the American Anabrus simplex and the Eu- 

 ropean Locustce oviposit in the ground like the Acridiidw. Others, 

 like many species of XipMdium and Orchelimum, oviposit in the pith of 

 easily penetrated twigs. According to Professor Eiley Phaneroptera 

 ciirvicauda lays its eggs "singly in the edges of leaves, between the 

 upper and lower cuticles." Other species, approaching Xipliidium ensi- 

 ferum like Conocephalus ensiger, lay their eggs between the root-leaves 

 and stems of various plants. The European Meconema varium, accord- 

 ing to Taschenberg, oviposits under bark scales and occasionally in the 

 galls of the Hymenopteron Teras tenninalis. Still other forms to which 

 our common Katydid {Microcentrum retinervis) belongs, lay their flat- 

 tened, dark colored eggs in regular rows on twigs, after previously 

 roughening the surface of the bark with their jaws. 



The structure of the ovipostor in Xipliidium ensiferum would seem to 

 indicate that, like other members of the genus, this species has been 

 in the habit of puncturing the tissues of plants till within compara- 

 tively recent times, when it found oviposition in the galls more advan- 

 tageous. So recent may be the acquisition of this habit that more ex- 

 tended investigation may perhaps show a tendency in some females to 

 puncture twigs, or oviposit, like Conocephalus , between the root-leaves 

 and stems of plants. 



The Orthbptera present many interesting questions in connection 

 with their habits of oviposition. Most of the species, excepting the 

 aberrant Phasmidw, oviposit in clusters, the eggs of which are arranged 

 in more or less regular rows. This habit is most strenuously adhered 

 to by the Blaitidce, though many species of Acridiidce, Gryllidce, Locust- 

 idce, and Ma7itidce are almost equally careful to deposit their eggs in 

 symmetrical series. 



During oviposition the two ovaries discharge their eggs alternately 

 in rhythmical sequence, the insect moving a short distance directly for- 

 ward after the extrusion of each egg or pair of eggs. For what pur- 

 pose this habit should have been preserved with such tenacity through 

 the long ages during which the Orthoptera have continued to people 

 our earth I am unable to conjecture, unless it be supposed that the 

 primitive species oviposited in portable capsules like those still made 

 by the Blattidce. The method of arranging eggs in two even and alter- 

 nating series practiced by members of this family is of advantage to 

 the insects, in that it renders the package more compact and more easily 

 carried, just as a box may be made to contain a given. number of cigars 

 or similarly shaped objects more easily when they are packed in regular 



