372 



TEXT-BOOK OF ENTOMOLOGY 



a 



in length, with a short and very slender duct opening externally at 

 the bottom of the pit (Scudder). 



In the Mantidse these seem to be genuine coxal glands, as there 

 is a pair situated between the coxae of the first pair of legs. An 

 evaginable organ like a wart, with a glandular appearance, occurs 

 on the hind femora of the Acrydiidse in a furrow on the under side, 

 into which the tibia fits, about one-fourth from the base (Psyche, 

 iii, p. 32). 



In the male cricket, the anal odoriferous glands are small lobes 

 opening into a reservoir on each side of the rectum (Dufour). Ho- 

 mologous glands also occur in the Coleoptera (Fig. 302, 1 and 317, s). 

 Most Hemiptera or bugs send out a foetid or nauseous odor due 

 to a fluid secreted by a single or double yellow or red pear-shaped 

 gland, situated in the middle of the mesothoracic segment, and 

 opening between the hinder or third pair of coxae. In Belostoma 



Leidy describes these glands as consisting 

 of two rather long co3cal tubes situated 

 in the metathorax, beneath the other vis- 

 cera, extending backwards into the ab- 

 domen, and opening between the coxse 

 of the third pair of legs. Locy states 

 that the smell arising from these glands 

 is pleasant, resembling that of well 

 ripened pears or bananas. Other bugs, 

 moreover, emit an agreeable odor, that 

 of Syromastes resembling that of a fine 

 bergamot pear. (Siebold.) The fluid 

 given out by the European fire-bug 

 (Pyrrhocoris apterus) has a sweetish 

 smell, like ether. In the nymph there 

 are three pairs of dorsal glands, on abdominal segments 2-5, which 

 are atrophied in the mature insect. In the bed-bug, the nymph has 

 three odoriferous glands each with paired openings in the three 

 basal abdominal segments respectively, and situated on the median 

 dorsal line, being arranged transversely at the edge of the tergites; 

 but after the last moult these are aborted, and replaced by the sternal 

 metathoracic glands (Kiinckel). Gissler has detected a pair of 

 glands in Lachmis strobi (Fig. 361). 



Anal glands of beetles. Certain beetles are endowed with eversi- 

 ble repugnatorial glands. Eleodes yigantea and E. dentipes of both 

 sexes are said by Gissler to possess these glands. When teased 

 " they stand on their anterior and middle legs, holding the abdomen 



FIG. 361. Glands (fir) of Lach- 

 nus ; ft-, "honey" wart. Gissler 

 del. 



