FILAEIA SANGUINIS HOMINIS IN THE MOSQUITO. 385 



posteriorly ; it was slightly constricted in the middle. After the slide had been mounted some 

 time, a shrinking of the contents showed the integument of the parasites very distinctly, all 

 exhibiting a marked doable outline. 



fig. 15. From the thorax of a mosquito the date of whose feeding could not be fixed, probably about 80 

 hours before examination. In its thorax two Filarice were found, one partly crushed, the other 

 perfect— as represented. Measurements T ]- " x ^Vo" anteriorly, and 8 ^ ff " posteriorly. It ex- 

 hibited occasionally spasmodic jerks. At the head a distinct double outline. An alimentary 

 line ran backwards some distance, becoming convoluted posteriorly, and gradually becoming 

 less distinct till it was lost at the middle third. Anus distinct, open, and emitting a few 

 granules. Tail distinct. Contents of the hody obscurely cellular, lobulated, granular. 



?i°-. 16. From thorax 97| hours after capture. A considerable number of Filarice found resembling 

 sketch. Body smooth in outline, plump, and healthy-looking. The mouth was four-lipped, 

 and a pharynx could be made out ; but no other trace of an alimentary canal unless in one 

 specimen in which a funnel-shaped anus was apparent in the usual situation. The tail was 

 delicate, but moved distinctly. There seemed to be a condensation of tissue near the surface of 

 the hody, especially about the waist. There was a shoulder and an anal bulging. Movement 

 of the lips was observed. Measurements T £ " x 1200"- 



Fig. 17. From thorax 97 hours after capture; about a dozen sausage-shaped Filarice found. Four lips 

 readily made out; alimentary line running from mouth to anus. Cellular matter escaping 

 from anus. Content.-; of body cellulo-granular, and very obscure. Tail small. Specimen 



measured i\ { ,"x - 7 J,„"- 



t Figs. 18, 19. From the thorax of a Filaria found dead (but recently living) 96 hours after capture. 

 ' Alimentary line very distinct. Body celluio-granular. Four lips rather pursed up. One 

 measured T f " X 7 }/. Many similar in this insect. 

 Fig 20 From thorax 144 hours after capture. In this particular insect eight such Filaria were found. 

 Mouth, alimentary canal, and anus, well marked in all. Tad was very faint, and it could 

 easily 'be ascertained that at this stage it was nearly entirely integumented. The longest 

 measured fa" x -gW • In it the cellular structure of the body was very apparent posteriorly ; 

 towards the°head the cell-outlines could not be made out, the tissues looking granular or homo- 

 geneous. The mouth was pursed up. No movement remarked; granular escape from anus 

 considerable. Alimentary line very thick, giving the impression that it was filled with some 

 dark substance. 



; Figs 21-23 From the thorax of a mosquito 128 hours after capture. In this insect about a dozen 

 advanced Filarice were found. They were nearly all straight, extended, with truncated posterior 

 ends tipped with a minute, delicate, tegumental tad. Mouth distinctly four-lipped. Shoulder 

 and anal bulging, and waist, inmost. Alimentary canal traceable from the mouth to anus in 

 some in others gradually losing itself about the middle of the body. Round this line nucleated 

 cells have ranged themselves. In fig. 21 a prolapsus of part of the intestine has occurred. 

 The body is filled with minute, clear, nucleated cells, in all the specimens. In 23, in addition 

 to the alimentary line, traces of what may be commencing organs of generation were seen; a 

 line could be followed from a point a little posterior to the head meandering backwards for some 

 little distance among the cells. Where this line opened on tbe surface a dimly indicated infun- 

 dibulum, which maybe vulva and vagina, was indicated. Outline of all distinctly double. 

 Fig 23 measured fa" X 5TjT j "j the others about fa" x t y and fa" x *fo". 

 Fig 24 From thorax 145 hours after capture. Eight Filarice in thorax far advanced in development. 

 ' The mouth and tail very evident. In some the tail was entirely integumental ; m others a 

 papilla from the body projected slightly into it-fig. 34; whilst in others the integument was 

 quite filled up with the same material that made up the bulk of the body-fig. 35. When first 



