64 



Atius opening in a slight ridge of tail, 0,372 

 mm. from posterior extremity. 



Female: Tail straight, funnel-shaped with 

 chitinoiis appendix, 0,030 mm. in length. 

 Vulva situated behind the middle part of 

 body, very prominent, cleft-like, with two 

 large lips, one anterior the other posterior. 

 Ovijector directed from the vulva towards 

 the cephalic extremity, dilated in the poste- 

 rior segment, followed by the vestibulum; 

 approximate length: 0,465 mm. Uterus short» 

 dichotomous, with diverging branches. Ova- 

 ries very large; ovarian loops reaching firs^ 

 part of intestine, but not exceeding anus. 



Eggs ellipsoid with very thin shell, still 

 in segmentation when laid; length: 0,083 

 mm.; width: 0,053 mm. 



Development. Unknown. 



Habitat. Intestine of Caranx lugubris, 

 POEY. 



Origin. Island of Trindade, Brazil. 



Material. The specimens studied were 

 taken from the helminthological collection 

 of the Instituto OSWALDO CRUZ (No 1491). 

 Five males and two females, preserved in 

 glycerine. 



CUCULLANUS DODSWORTHI n.sp.(l) 



Plate 45, figs. I e 2. Plate 46, figs. 3 c 4- 



J j length: 9,54 mm.; width: 



Dimensions I ^-^^^ "^'"• 



. 9 ! length: 4,4 mm.; width; 0,445 



I mm. 



Body white, filiform, rectilinear, tape- 

 ring at extremities; posterior part curved 

 like a hook, in males only. Moderately 

 thick cuticle transversally striated; the stria- 

 tions are 0,0037 mm. from one another; 

 longitudinal striations extremely fine and 

 close together in optical cut, the cuticle 

 ?eems to be formed of two layers, the ex- 

 ternal one almost hyaline, the internal one 

 of more or less the same thickness, slightly 

 granulated, separated from one another by 

 an exceedingly refractory line; the thickness 



(1) Species dedic.ited to my friend and colieauiie 

 Pr. H, TOLEDO DODSWORTH JUNIOR. 



of cuticle: 0,0088 mm. Anterior extremity 

 cylindro-conical, when seen dorso-ventrally 

 apparently sub-quadrangular. Lateral alae 

 wanting. At the height of the junction of 

 the oesophagus with intestine, a pair of ce- 

 phalic papillae which are very distinct when 

 the nematode is seen from the side. Nerve 

 collar at the junction of anterior fourth and 

 posterior three-fourths of oesophagus, 0,372 

 mm, from cephalic extremity. Mouth formed 

 by two thick equal lobes, each of which 

 has three equal, external papillae, one dor- 

 sal, one ventral and one median; on inter- 

 nal surface each lip has two chitinous sheets 

 of equal dimensions with reticular structu- 

 re and dentate or serrate border; denticles 

 like a short bayonet, the cutting sheets 

 adhering by the posterior rim to the lobes' 

 two-thirds of them free, and curved inwards 

 in the oral cavity, so that, when seen in a 

 dorso-ventral direction, they look like two 

 lips forming the curves of a circle thus 

 closing the buccal orifice; a fine membrane, 

 part of the cuticle, unites the lobes. 



Diameter of cephalic extremity ; 0,270 

 mm.; width of lobes: 0,095 mi-i. 



Oesophagus rectilinear, forming a large 

 amphora-like dilatation in the buccal cavity, 

 turned ventrally, thus forming a sub-oral 

 capsule; in this part of oesophagus, the 

 walls are very thick with strong transversal 

 muscles; the inner wall is clothed with chitin; 

 oesophagus rectilinear behind this dilatation, 

 the posterior extremity club-shaped; walls 

 of oesophagus muscular; gland less; propor- 

 tion of oesophagus to body 1:7 in female, 

 and 1:0 in nale; length of oesophagus: 

 1,335 mm. Sub-oral dilatation, length: 0,279 

 mm.; width: 0,195 mm. Intestine dilated in 

 initial portion which fills here rnore than 

 two-thirds of the visceral cavity ; the intes- 

 tine before reaching the posterior extremity 

 shows a sphincter which connects it with a 

 small rectum ; this is curved ventrally towards 

 the anus which is generally on a slight 

 ridge, especially accentuated in females. 



Male: Accessory piece cylindroid, 0,114 

 mm. long; 0,015 mm. wide. Anus 0,186 mm. 

 from posterior extremity of body. 



