1921] Wheeler: Some Social Beetles 61 



tened posterior border of the body, and, on the dorsal surface, 

 two pairs of peculiar organs which have the form of transverse, 

 mouth-like slits with thick lips. One pair of these organs is 

 situated near the posterior corners of the head, the other between 

 the sixth and seventh abdominal segments. Coccidologists have 

 long been familiar with these organs in certain genera of mealy- 

 bugs of the subfamily Eriococcinje, and have called them "eye- 

 like glands" "cicatrices," "osteoliform or labiate fovese," or 

 "dorsal ostioles." sulc called them "adipopugnatorische Organe" 

 and MacGillivray has recently dubbed the two pairs "cephalabise" 

 and "caudalabiae" respectively, terms so barbarous that they 

 make one's flesh creep. I shall call them anterior and posterior 

 ostioles. Berlese regarded them as apodemes, or invaginations 

 of the integument for the insertion of muscles. Comstock, New- 

 stead, §ulc and MacGillivray regard them as glands. In 1882 

 Comstock stated that he had "observed in DacUjlopius a pair of 

 openings on the dorsal side of the sixth abdominal segment, 

 which are evidently homologous with the honey tubes of Aphi- 

 didse. A female mealy-bug was gently rubbed near the caudal 

 end of the body, when suddenly there appeared two drops of a 

 clear fluid, resembling in appearance the honey-dew of plant- 

 lice. This experiment was repeated many times and with many 

 specimens. Mr. Pergande assures me that he has observed a 

 similar excretion from a pair of openings on the cephalic mar- 

 gin of the first thoracic segment." Comstock was, of course, 

 under the erroneous impression that the honey-dew of aphids 

 is a secretion of the cornicles instead of being the excrement of 

 the insects and therefore extruded from the anus. According 

 to MacGillivray : • "There can frequently be observed on living 

 specimens a small globule of a clear fluid over the mouth of each 

 labia, more frequently the caudalabise than the cephalabise, so 

 that they are probably also glandular in structure as suggested 

 by Comstock. For, as he suggested, when the specimens are 

 stroked with a pencil or dissecting needle, the insect will hump 

 up its back and extrude a globule of liquid. The insect is unable 

 to repeat this operation until the pocket is again filled with the 

 clear fluid. Specimens have been observed to extrude globules 

 from all four labise at the same time. The labise undoubtedly 

 have a glandular function which is probably of later origin than 

 their earlier function, a parademe for the attachment of muscles." 



