NO. 7 PROTFXTIVE ADAPTATIONS McATEE 4I 



(Copeia. 1930, p. 45) says of 400 young toads examined, " Thrips 

 formed 10. i per cent of the food, but were found in all hut a few 

 stomachs. These small insects appear to be a staple article of diet 

 for young Bufo." 



Discussion. — Thrips are too small for most birds to notice, but 

 considering our ignorance of the subject, the notes on enemies given 

 indicate that they have foes, the character and number of which, 

 probably as in other cases, are regulated largely by the factor of 

 availability. 



RHYNCIIOTA (bUGS, CICADAS, LEAFIIOPPERS, SCALE INSECTS ) 



For the reason that the term Hemiptera in a broad sense was used 

 for about one-fourth of all the identifications of Rhynchota, it is not 

 practicable entirely to separate Ileteroptera and Homoptera. However 

 the identifications of these groups are distributed as far as possible to 

 families in the tables presented. In using these tables, it should be 

 kept in mind that could the incomplete determinations have been dis- 

 tributed, the figures would average about a fourth higher throughout. 



Protective adaptations. — The popular expression ' a nasty bug ' 

 tmdoubtedly has reference, in most instances, to insects of this order, 

 many of which produce scents disagreeable to human senses. Theorists 

 have assumed these must also be repulsive to animal ])redators, a 

 doctrine briefly stated in the following quotation from E. 13. Poulton : 

 " The Heteroptera (Hemiptera) are obviously, as a whole, a specially 

 protected group, commonly defended by taste or smell from large 

 numbers of insect-eating animals." ' 



A great series of Heteroptera are more or less aquatic in habit and 

 thus are screened from the attacks of purely terrestrial enemies. 

 Some are very active, as the Saldidae and many Miridae ; some are 

 said to be " mimics," as for example immature Nabidae resembling 

 ants and certain Reduviidae resembling wasps. 



Mimicry, so-called, is exemphfied among the Homoptera, also, as 

 some Fulgoridae are considered to resemble Lepidoptera in appear- 

 ance. The Membracidae with a host of bizarre forms, are thought to 

 present cases of mimicry to ants, and of resemblance to thorns and 

 seed pods of plants. One author further remarks : " Evidently the 

 strong pronotal processes, which are often sharp and hard enough to 

 pierce the skin if the insect is seized suddenly, are unpalatable and 

 irritating."' Quoting Poulton again (op. cit., p. 4) : "Allusion must 



' In Buckton, G. B., A monograph of the Membracidae, separate, p. 3, kjoj. 

 ■ Funkhouser, W. D., Mem. 11, Cornell Univ. Agr. Exp. Sta., p. 417, June, 

 1917. 



