TEXAS NATURE OBSERVATIONS AND REMINISCENCES. 67 



the bat is an insect destroyer. In 

 the year 1889 Captain Reichards 

 of D'Hanis, himself an academic 

 zoologist of the old school and 

 close observer of Texas nature ob- 

 jects, had sent to the writer sev- 

 eral samples of the bat guano 

 gathered from the large bat caves 

 of Frio County, for a closer micro- 

 scopic examination, and I pre- 

 pared for his ovirn satisfaction, 

 about ten photo microscopic views 

 of the guano. These views re- 

 vealed throughout extensively 

 remnants of predigested insects 

 of various variety, but mostly 

 remnants of gnats, mosquitoes, 

 flies, moths, spiders and beetles. 



In most of the microscopic slides' 

 examined the multiprisms.- of in- 

 sect eyes, mostly of gnats, mos- 

 quitoes, flies and beetles, could be 

 seen. There were no vegetable tis- 

 sues present. The scales of moths 

 and smaller insects were numer- 

 ous, as also remnants of insect 

 legs and the body shields, claws, 

 parts of antenae, etc., of various 

 insects. 



It is thus shown conclusively 

 that that little "obnoxious" look- 

 ing mammal — the bat — is a very 

 useful insect destroyer. 



Finally attention may be called 

 to an insect among insect killers, 

 — the dragon fly, or mosquito 

 hawk. This is another sanitary 

 scavenger in its way, as it feeds on 

 smaller insects such as mosquitoes 

 and gnats, of which the banks of 

 rivulets and tanks and other wa- 

 tering places abound, especially 

 like out at West End Lake or at 

 Mitchell 's Lake, south of San An- 

 tonio, where there is a large sur- 

 face of water surrounded with 

 plenty of vegetation. Here mil- 

 lions of the mosquito hawks can 

 be seen in all forms and colors 

 and of all eenera. Some are beau- 

 tifully striped and all are a lively 

 set of insects, and, by reason of 

 their sharp eye sight, hard to catch. 



In its larval state the 'dragon 

 fly has always been an interesting 



study to naturalists. The female 

 insect deposits her eggs in masses 

 — up to a hundred eggs. She gen- 

 erally hovers a considerable time 

 over a certain favored water place 

 — often over a small, stagnating 

 and well demarcated pool of water 

 near an outlet of some creek, tank 

 or lake, rapidly dipping the apex 

 of her abdomen into the water, 

 when her eggs gravitate to the 

 bottom of the water. Many ob- 

 servers also have seen them creep 

 along the stem of a water plant 

 into the water and thus lay their 

 esrgs on the bottom. When ma- 

 tured the peculiarly shaped larvae,, 

 after several shedding processes, 

 creep outside the water and ad- 

 here to the stem of a plant or tree, 

 and after further development, the 

 younsr dragon fly gradually creeps 

 through an opening in the upper 

 aperture of its primary anatomy 

 or hull— first with its head parts, 

 then the front feet and ultimately 

 with its entire body, and always to 

 a curved position of its body. Its 

 wings are now very delicate, but. 

 they soon dry entirely, when they 

 swiftly fly in search of their in- 

 sect food. 



The small minnow fish, fully 

 described elsewhere is also * a 

 great enemy to the eggs of the 

 dragon fly, as well as those of the 

 mosquito and other aquatic in- 

 sects. To Dr. Campbell the 

 writer is indebted for a sample of 

 the dragon fly eggs, of which I 

 prepared several microscopic 

 views, showing' the delicate long 

 and oval shaped eggs highly mag- 

 nified — normally not being larger 

 Jhan the size of a flea. 



The wings and the head of a 

 dragon fly with its proportianate- 

 yl enormous eye globes and the 

 mouth larts of this insect are an 

 interesting study, the latter being 

 su^^lied with strong, serrated man- 

 dibles, with which they grab and 

 chew their insect victims, and also 

 the eye capsule is a most interest- 

 ing object under the microscope. 



