12 PROCEEDIlSrGS OF THE NATIONAL MUSEUM vol.73 



of the anatomy are shown in the figures. Laurer's canal opens dor- 

 sally on the median line on a level with the posterior border of the 

 ovary. It passes laterad along the dorsal border of the ovary, then 

 turns medio-ventrad to the uterus, the earlier portions of which con- 

 tain sperm. The excretorj^ vessel behind the second testis is spacious. 

 It divides at the posterior end of the second testis. The exact num- 

 ber of oral spines could not be made out in the balsam mount. There 

 are at least 27. There is a single row, except at the lateral angles. 

 (Fig. 23, sketched from a transverse section.) The longest spine 

 measured 0.051 in length and 0.018 in breadth, shorter spine 0.039 in 

 length and 0.012 in breadth. A striking character in the structure 

 of the body wall is the layer of longitudinal muscle fibers. These 

 are indicated in the sketches of transverse sections. (Figs. 32, 33.) 



Dimensions of specimen mounted in balsam: Length 9 mm.; 

 breadth, at level of ventral sucker 0.63, at ovary 1.17, 1 millimeter 

 from posterior end 0.91; oral sucker, length 0.11, breadth 0.10; 

 pharynx, length 0.09, breadth 0.056; ventral sucker, diameter 0.38; 

 distance of anterior border of ventral sucker from anterior end 0.35 ; 

 diameter of ovary 0.28; first testis, length 1.12, breadth 0.35; second 

 testis, length 1.05, breadth 0.40. In a series of sections: Diameter 

 of oral sucker 0.12; pharynx, length 0.10, breadth 0.08: diameter of 

 ventral sucker 0.31. 



Ty2)e.—C-At. No. 7925, U.S.N.M. 



BECORD OF COLLECTION 



Oideinia deglandi. 



1914, June 2. 2. The living worms red, according to record of Vinal 

 N. Edwards, collector. 



MESORCHIS PSEUDOECHINATUS (Olsson) 



Figures 34-42 



1876. Distomum pseudoecMnatum Olsson, Svensk, Vetensk. Akad. Handl., vol. 



14, p. 21, pi. 4, figs. 45^9. 

 1892. EcJiinostoinuni pscudocrhinaUwi Olssou Stossich, Boll. See. adriat. So. 



nat., Trieste, p. 166 (p. 24 of reprint). 



1898. MUHLING, Arch. Naturg., Jg. 64, vol. 1, p. 21. 



1899. Echinostomum pseudoecMnatum Olsson Stossich, Boll. Soc. adriat. Sc. 



nat., Trieste, vol. 19, p. 13. 

 1899. Echinostomum pseudoechinattim (Olsspn) Looss, Zoolog. Jahrb., vol 12, 



Syst., pp. 685-686, pi. 25, figs. 11, 12, 15a-. 

 1!»09. Echinostomum {Mcsnrchis) pseudoecMnatum (Olsson) Dietz, Zool. Anz., 



vol. 34, p. ia3. 

 1909. MesorcMs pseudoechinatus (Olsson) Dietz, Inaug, Diss., Konigsberg, 



p. 31. 

 1910. , Zool. Jahrb. Sup. 12, p. 451-452. 



