1916] Breeding Habits of the Orthoptera 121 



squeak, hearing does not seem to be so important. Among the 

 Locustidas are found species which are not only wingless but 

 have no means of making sounds. These are nocturnal and 

 representative. Ceuthophilus stygius, a species living in the 

 caves of Indiana, has eyes that have become somewhat rudi- 

 mentary. Since it breeds "far back beyond the reach of any 

 rays of Hght," (Blatchley, '02) and is devoid of hearing organs^ 

 the only senses left to it for its sexual activities are those of 

 smell and touch. In Ceuthophilus latens the writer found that 

 although the eyes are well developed they are not used in the^ 

 sexual activities of the animal, sex discrimination depending 

 upon contact and possibly odor. In the Locustidse then, sex 

 discrimination is accomplished in some cases by contact (perhaps 

 "contact odor") alone, in others by contact and sight and in 

 still others by contact, sight and hearing. 



The true crickets, or Gryllidae, present nearly as wide a 

 variation in their preliminary movements as do the Locustidae. 

 Chirping is a common habit with both the nocturnal and the 

 diurnal crickets and is without doubt a sex call. In some of the 

 nocturnal forms the sense of sight is evidently used but little 

 and the sense of hearing is relatively important. The field and 

 ground crickets have similar copulating habits. After a female 

 has approached in response to the call of the male the usual 

 fencing with the antennas ensues and then the male, turning 

 around and raising his wings, invites the female to mount. The 

 tree cricket (Oecanthus) has been much observed and its habits 

 described in detail. The female becomes greatly excited upon 

 hearing the call of the male and in going to him in response to 

 the call seems to be directed by the sound. (Jensen, 1908.) 



The mole cricket (subfamily Gryllotalpinae) breeds under- 

 ground in tunnels which it constructs. (Baumgartner, '10.) 

 Although it is obliged to carry on all its mating activities in the 

 dark, the loss of opportunity to use the sense of sight is com- 

 pensated for by the presence of a chirping organ in the female. 

 She answers the call of the male until they have come into con- 

 tact, and the problem of their uniting is simplified. 



Sex recognition in the Gryllidae is accomplished in all cases 

 with the aid of the sense of hearing and in some without the 

 possibility of aid by sight. How much of a part actual contact 

 plays it is difficult to say, but the movements that would 

 indicate a sexual excitement frequently are begun with the aid 



