34 TEXAS NATURE OBSERVATIONS AND REMINISOENOES. 



similar stinging implements, 

 though varying in certain genera. 



The stinging implements of most 

 insects, in the inactive state, are 

 •concealed in a hollow sheath along 

 the base and interior part of the 

 proboscis, which comprises the 

 flexible suction tube or tongue, 

 in some insects. ■ When in the 



Photomicrograph of a Mosquito's Head 

 AND Stinging Implembnts 



act of stinging the needle-pointed 

 daggers are separated from the 

 hollow sheath and, through muscu- 

 lar action at the base parts and 

 rythmical motions are gradually 

 pierced through the skin up to 

 the. capillary layers, when blood 

 is liberated and absorbed through 

 suction. 



The original photograph of a 

 mounted mosquitoe's mouth parts 

 shows one of the daggers inside the 

 central sheath, and two slightly 

 curved daggers outside of same. The 

 knoblike end part of this broad; hol- 

 low proboscis is jointed at its lower 

 part, and consists of two hairy pads, 

 which is also set in motion by the 

 mosquito during the suction act, 



and serves to accumulate and ab- 

 sorb the blood particles. 



It is quite well known that a 

 variety of insects, in particular 

 blood sucking insects, are liable 

 to transmit morbid tissue-pro- 

 ducts and pathogenic micro orga- 

 ism upoii man and animals. This 

 is the case with some species of 

 flies, which can transmit anthrax 

 bacilli, after feeding on some such 

 diseased animal, and produce the 

 malignant pustule; and the horsefly 

 with its powerful developed mouth- 

 parts of daggers and lancets, scari- 

 fies the thick hide of animals 

 until blood oozes from the wounds, 

 and these scarified places often 

 suppurate later on, and are then 

 infested by other insects, especially 

 the blowfly, which deposits numer- 

 ous eggs, from which the screw- 

 worms develop; or the small gnat- 

 flies, and mosquitoes, feed on 

 the suppurating surfaces, trans- 

 mitting pus and blood corpuscels,' 

 etc., upon other animals or man,— ' 

 for instance, opthalmitis, etc., 

 when coming in contact with the 

 conjunctiva of the eye. Ticks, 

 and especially the common bedbugs 

 are also on record as bacteria 

 transmitters, — notably also the tu- 

 bercle bacillus from phthisical pati- 

 ents; and the cattle tick, it is 



EyELENs Segments op the Texas Horsefly 



quite conclusively proven, pro- 

 duces the so-called Texas cattle 

 fever through inoculation. 



