No. 5 meserve: monogenetic trematodes 43 



Diclidophora caulolatili, new species 



(Plate 5, figs. 13-15) 



Host: Caulolatilus princeps (Jenyns) 



Location: Gills 



Locality: Tagus Cove, Albemarle and Chatham Islands, 



Galapagos Islands 

 Number: 2 



Body lanceolate, somewhat pointed and tapering at the anterior 

 end, 4.506 to 5.970 mm. in length by 0.784 to LI 70 mm. at greatest 

 width. Posterior haptor approximately one third total body length 

 with eight elliptical posterior suckers on tips of relatively long pedi- 

 cels which are approximately equal in length. Posterior pair of 

 suckers approximately one half diameter of other three pairs. An- 

 terior pair of posterior suckers 0.339 by 0.373 mm. in length by 

 0.339 to 0.407 mm. in width, chitinous skeleton (fig. 14) complex 

 with eight chitinous pieces and four spines, eight pieces, one ventral, 

 broad, Y-shaped piece, one pair of short pieces lateral to Y-shaped 

 rod, one pair joining these and imbedded in the lateral wall of the 

 sucker, a single upright piece with a pair of curved lateral rods 

 joining it at the distal end; four spines with bulbous bases and fine 

 recurved points at top of sucker with faces imbedded in sucker wall 

 and having exposed sharp points. Anterior suckers relatively large, 

 without membranous septa, elliptical, longer than broad, 0.127 to 

 0.169 mm. in length by 0.084 to 0.135 mm. in width. Pharynx bulb- 

 shaped, longer than wide, 0.080 to 0.120 mm. in length by 0.044 by 

 0.076 mm. in width. Esophagus relatively long and slender, bifur- 

 cating just in front of genital pore to form intestinal limbs with 

 lateral branches. Testes smooth, almost spherical, extending from 

 ovary to posterior haptor, fifty-six to sixty-five in number. Cirrus 

 armed with thirteen double recurved hooks. Cirrus hooks 0.012 to 

 0.016 mm. in length. Genital pore just posterior to bifurcation of 

 esophagus well forward in the anterior part of the worm on ventral 

 side in mid-line. The distance from anterior end of worm to genital 

 pore is 0.271 to 0.424 mm. Size of opening of genital pore is 0.02 

 mm., diameter of outer rim 0.06 mm. Ovary slightly to left side of 

 mid-line in middle part of body proper, vertical arm approximately 

 twice diameter of horizontal arm, posterior arm at right angles to 

 upright vertical arm and bent in form of a C with ends open and 

 directed posteriorly. Seminal receptacle large to right of ovary, C- 



