SEEING BY AID OF THE LENS 



97 



beetle but otherwise is of a similar, red- 

 dish brown color and very active in its 

 movements. Both the tobacco and 

 drug-store beetle, it seems, undergo 

 about one and the same cycle of de- 

 velopment and when the ova are de- 

 posited in favorable media of a powder- 

 ed nature, such as rhubarb, orris root, 

 slippery elm, linseed meal, tobacco or 

 cayenne pepper powder, the ovum 

 transforming into the larval state is 

 encysted into the globular forms sim- 

 ilar to these seen in Fig. 4 and similar 

 to the genesis of other forms of insect 

 life. 



The main characteristic features to 

 determine the genus and the difference 

 between the drug-store, and the to- 

 bacco beetle, larva are the clawed feet 

 and the jaws of the head parts of the 

 tobacco beetle, the single small claw 

 being sharply outlined on high pow T er 

 examination as shown by the photo- 

 micrograph herewith representing a 

 larva freshly taken from the middle 

 foldings of a cigar and immediately 

 photographed by the writer with par- 

 ticles of tobacco leaf detritus surround- 

 ing the larva. 



The harm these minute insects are 

 liable to do to tobacco, food stuffs and 

 drugs is often enormous and they are 

 often a great nlague to dealers in to- 

 bacco and drugs and because of their 

 minute size and rapid movements are 

 difficult to exterminate. Being winged 

 as other beetles, they can fly and 

 migrate to distant places and there 

 perform the same havoc and multiply 

 enormously. 



Both these minute beetles above des- 

 cribed tally with the observations of 

 Dr. L. O. Howard, (Farmer's Bulletin 

 120) and Dr. F. H. Chittenden (Bull- 

 etin No. 4, Divis. Entom. U. S. De- 

 partment of Agriculture) but in our 

 case the matter is the more interesting 

 having found and depicted the larvae 

 situ and the larva of the drug store 

 beetle encapsulated in the peculiar 

 globular cocoons described and illus- 

 trated therein. Dr. Chittenden says 

 in regard to the tobacco beetle, "As 

 a tobacco feeder it outranks that 

 species (the drug store beetle) and also 

 appears to favor certain medicinal 



plants not so often affected by the 

 Sitodrepa (drug-store beetle. 



"Of household supplies it has been 

 found infesting cayenne pepper, gin- 

 ger, rhubarb, rice, figs, yeast cakes 

 and prepared fish food. It has been re- 

 ported as destructive to silk and plush 



FIG 5. 

 PHOTO-MICROGRAPH OF LARVAL TO- 

 BACCO BEETLE. 

 In its natural state, surrounded by tobacco 

 leaf remnants. Considerably magnified 



upholstery and the past year did con- 

 siderable damage to dried" and preserv- 

 ed herbarium specimens in Washing- 

 ton. Of drugs it is partial to ergot and 

 turmeric and tobacco it devours in 

 every form." 



The druggists and tobacco dealers 

 throughout the country undoubtedly 

 are familiar with the above minute 

 pests and these memoranda concern- 

 ing them, I believe, will be appreciated 

 by readers of The Guide to Nature. 



"A world of wonder lies around us." 

 That saying is so trite that the truth 

 in it is too often not realized. Many 

 people wear eyeglasses because the 

 ordinary newspaper and business mat- 

 ters of life cannot be utilized without 

 this commonplace optical aid. . But 

 why not as commonly use a pocket 

 microscope? Rightly applied it .will 

 give much pleasure and instruction. 

 It is a life ticket to a wonderful mus- 

 eum and menagerie. 



