» 



OF THE NEMATOIDS, PAEASITIC AND FREE. 029 



Fig. 20. Posterior extremity of male of same species, lateral aspect, showing the scries 

 of suctorial papilla) of one side of body (a, a, a, a) ; b, one of posterior latero- 

 ventral pores ; c, larger of two spicules, protixided. 



Fig. 21. Magnified view of surface of integument, corresponding to one of these ventral 

 papillaj : — a, central aperture leading to apex of papilla ; I/, slightly concave 

 depression in which it is situated ; c, linear markings of integunient. 



Fig. 22. One of bladder-like developments from muscle-cell of Ascaris lumiricoides, 

 highly magnified*. 



Fig. 23. Anterior portion of body of Ascaris megalocephala slit open in the dorsal 

 line, the head-lobes cut off and oesophagus removed: — a, a, lateral bands; 

 h, dorsal median line ; c, ventral median line ; d, position of oesophageal band 

 of nervous system ; e, arch of excretory vessels ; f, mid-ventral orifice. 



PLATE XXIII. 



Fig. 1. Transverse section of the integument of Ascaris lumhricoides posterior to the 

 termination of oesophagus: — a, chitinous portion of integument; h, deep 

 cellulo-granular layer; c, c, median lines; d, d, lateral bands; e, e, axial 

 vessels or ducts. 



Fig. 2. Transverse section of the entire animal, slightly anterior in position to that of 

 last figure : — letters from a — e same as in last figure ; f, f, f, f, sections of 

 the four great longitudinal muscular bands ; g, (j, g, g, the four sets of trans- 

 verse muscular fibres, proceeding from the muscle-cells to the median lines ; 

 h, h, bladder-like developments from the muscle-cells ; /, transverse section 

 of intestine. 



Fig. 3. Transverse section of the male about IJ inch from its posterior extremity. 

 Letters a-i same as in last figure. The lateral bands are here seen above 

 the median horizontal plane of the body, and arising from them are strong 

 muscular processes, latero-ventral {k, k), chiefly proceeding to the muscles on 

 either side of the mid-ventral line ; I, L latero-ventral impilla; at their gi-eatest 

 distance from one another; m, male genital tube. The axial canal of the 

 lateral band cannot be recognized in transverse sections of this region 



Fig. 4. Transverse section of the male a short distance above the ano-genital cleft. 

 Letters of reference as in fig. 3, with the addition of n, n, for the two unequal- 

 sized male spicules, and o, o, the sheaths in which they are contained. The 

 most notable points in this section are the deviation from the cylindrical 

 form, the almost dorsal position of the lateral bands, the strength and bulk 

 of the latero-ventral muscles, and the absence of the ordinary transverse pro- 

 cesses, together with the extreme thickening of the walls of the genital tube, 



• This figure ought to have followed fig. 9 of the next Plate, and fig. 23 of this Plate should have formed 

 a part of Plate XXV. 



