494 



ORGANIC MATERIA MEDICA AND PHARMACOGNOSY 



The order of wingless insects Thysanura, which includes the "fish- 

 moths," those active scale-covered little creatures of the household, is 

 represented by a member of the genus Lepisma (probably saccharina) (see 

 Fig. 273), which I have found in jars of mezereon bark and Socotrine aloes. 



Finally, in jars of gall the pharmacist may find numerous little four- 

 winged, compact-bodied "flies," which are not, however, attacking his 

 stores, but which are only the insects which produced the galls, now issuing 

 from them. These little insects (see Fig. 274) are Hymenoptera, belong- 

 ing to the genus Cynips. The pharmacist may find other Hymenoptera 

 (distinguished by having four clear membranous wings with almost no 



FIG. 272. Atropos divin- 

 atoria Fab. (Original.) 



FIG. 273. Lepis- 

 ma saccharina 

 Linn6. (Walk- 

 er.) 



FIG. 274. Cynips. (Orig- 

 inal.) 



veins in them, see Fig. 274) in his jars and cans; but these insects are his 

 benefactors. They are parasitic on the beetles and other insect pests 

 which are feeding on the drugs, and thus do much good. Their eggs are 

 laid on the body of the grub of the drug-eating beetle, and the young 

 hymenopteron, on hatching, eats its way into the beetle-grub and lives 

 there at the expense of its host. 



REMEDIES 



Coming now to the matter of remedies, a reviewing of the notes thus 

 far presented shows that beetles are the most serious and numerous of 

 drug pests, and that practically only insects which have biting mouth 

 parts are injurious. In fighting insects with biting mouth parts the com- : 

 mon means employed by entomologists is to cover the substance attacked 

 (usually the green foliage of plants) with a thin coating of arsenic, by 



