ENTOZOA. 105 



processes, or penes, which are connected together at tlieir origin by a 

 cordiform glandular body, representing a prostate or vesicula semi- 

 nalis. The external orifices of the male apparatus, according to 

 Miram, are two in number^ and are situated on the dorsal aspect of 

 the body just behind the head. Diesing, however, describes the male 

 Pentastoma as having only a single penis, which protrudes just 

 behind or below the oral aperture. 



The female generative organs of the Linguatula tcenioides present 

 a structure in some respects analogous to that of the Distotna per- 

 latum : the ovary {^fig. 45. ii) is a part distinct from the tubular ovi- 

 duct, and is attached to the integument or parietes of the body, extend- 

 ing down the middle of the dorsal aspect. It consists of a thin stratum 

 of minute granules, clustered in a ramified form to minute white 

 tubes, which converge and ultimately unite to form two oviducts. 

 These (o, 6) proceed from the anterior extremity of the ovary, diverge, 

 pass on each side of the alimentary canal, and unite beneath the 

 origins of the nerves of the body, so as to surround the oesophagus and 

 these nerves as in a loop. The single tube (jo) formed by the union 

 of the two oviducts above described, descends, winding round the ali- 

 mentary canal in numerous coils, and terminates at the anal extremity 

 of the body. But, besides receiving the ova from the two tubes, the 

 single canal communicates at its commencement with two elongated 

 pyriform sacs (m, m), which receive from the male, in coitu, the semen, 

 and convey it into the oviduct, with the addition of a mucous secretion. 



The male organs in the Nematoidea consist of a single and simple, 

 slender, elongated tube {^fig. 44, e, e', /), or testis under its most 

 elementary form of a sperm-duct, which is merely a contracted con- 

 tinuation of the tubular testis of a seminal reservoir, which is a wider 

 part of the same tube, and of a single or double intromittent spicu- 

 lum with its prepuce, or bursa. 



The spiculum is simple in the genus Filaria. According to the 

 observations of Dr. Leblond*, the male-duct in the Filaria papillosa 

 terminates at the anterior extremity of the body, close to the mouth. 

 From this aperture the slender duct, after a slight contortion, is 

 continued straight down the body to a dilated elongated sac, which 

 represents the testis. In the Filaria attenuata the blind end or 

 beginning of the testis is bifurcate. 



In the Trichocephalus dispar the testis, a single tortuous tubule, 

 commences by a blind extremity near the rectum, passes forwards to 

 a dilated seminal receptacle at the anterior part of the thick portion 

 of the body, from which it bends backwards nearly the whole length 

 of the thick part, constricted at irregular intervals, and terminating 



* LXXXIP. p. 20. pi. 3. f. 1. 



