the middle with the posterior third of the body, this 

 is considerably dilated. Stripping off the expansion, 

 the main mass of the viscera, consisting largely of 

 the large dark red blood sacs of the alimentary canal, 

 are exposed. By caref Tilly tmravelling these, the ar- 

 rangement of long diverticula , described later, can 

 be made out. Lying upon the diverticula in the poste- 

 rior portion of the body is the ovary , studded with 

 developing ova. Upon either side of the ovary are 

 the coiled oviducts , and in the middle line is the large 

 conspiciious bilobed spermatheca (uterus ). In almost 

 every region of the body a portion of the thin coiled 

 malpighian tubules will be found. Behind the sperma- 

 theca is an opaque white organ, having very thin sac- 

 cular walls and filled with characteristic white secre- 

 tion from the malpighian tubules. This is the rectum 

 (rectal ampulla ), which in ticks serves as an excretory 

 bladder. By displacing the diverticula from the extreme 

 anterior portion of the body a bilobed glandular organ, 

 the cephalic gland (gene 's organ ) is displayed. Further 

 back, the bulboxis eridFof the cheliceres with radiating 

 muscular fibres are seen. Around them will be noticed 

 the ringlike chitinous fold at the base of the rostrum. 

 By displacing to one side the whole of the anterior and 

 lateral diverticula, a member of further structures are 

 apparent. Passing in from the stigmatic (spiracular) 

 openings is a leash of tracheal branches, of which the 

 large anterior ventral trachea is the most conspicuous. 

 Lying upon the origin of the first and second legs is 

 the large racemose gland which functions as the salivary 

 gland in ticks. Lifting this gland by its posterior 

 extremity, which lies on the anterior ventral trachea, 

 and tracing it forward, the short salivary duct will be 

 apparent entering the ringlike fold of chitin, already 

 mentioned, immediately beneath the cheliceres. Lying 

 partly under the salivary gland, and partly internal 

 to this structure is (the large, saccular coxal organ ) 

 conspicuous from the number of tracheae which supply it, 



'"By careful examination, the delicate, colorless 

 esophagus can be made out entering the lower surface of 

 the large median blood sac of the alimentary canal, 

 whilst lying behind the spermatheca is the fine hair- 

 like termination of the sac in the rectum. To the rec- 



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