686 PATAGONIAN EXPEDITIONS I ZOOLOGY. 



spacious stomach which reaches from XIV to XIX inclusive. The stomach 

 increases in diameter to about XVII, behind which a constriction occurs, 

 followed by a rather conspicuous sacculation in XIX, probably represent- 

 ing the posterior gastric caeca which, however, do not extend at all caudad. 

 Indeed there are no distinct gastric casca whatever. Four pairs of short, 

 rather wide intestinal casca are crowded into XXI and XXII and are fol- 

 lowed after a constriction by a somewhat bulbous dilatation. 



G. michalseni is represented by a larger number of specimens than 

 any other of the six species included in the collection. 



No. 3. " In and near drying-up pools on high divide, 50 miles north of 

 Rio Chico, near base of Cordilleras." 36 specimens. 



No. 5. "Spring on Rio Chico, 15 miles above Sierra Oveja." 2 speci- 

 mens. 



No. ii. "Small running stream south side of Rio Chico, 15 miles 

 above Sierra Oveja." i specimen. 



No. 15. "Spring on Rio Chico, 25 miles below Sierra Ventana, Feb., 

 1899." 20 specimens. 



No. 30. "Drying-up pool, banks of Arroyo Eke. Alt. 1,750 ft, Mar. 

 22, 1898." 34 specimens. 



No. 35. " Spring near base of Andes, 65 miles north of Rio Chico. 

 Altitude 2,400 ft, Feb., 1899." 20 specimens. 



No. 38. " Spring on Rio Chico, 25 miles above Sierra Ventana, Mar., 

 1898." i specimen. 



No. 43. "Drying-up pools near Arroyo Eke, altitude 2,100 ft, Feb., 

 1899." 3 specimens. 



No. 48. " Rio Blanco." 3 specimens. 



" In spring on Rio Chico." i specimen. 



HEMICLEPSIS TESSELLATA (Miiller) Veydovsky. 



A single individual, which is in nowise distinguishable from this well- 

 known European species, was collected on the Rio Chico. 



In demonstrating the identity of Theromyzon pallens Philippi with this 

 species Blanchard has already shown that its range extends in South 

 America as far south as Chili. Inasmuch as it is widely distributed, 

 though by no means common, in North America, it may now be expected to 

 occur generally over the American continent. Hemiclepsis tessellata is an 

 excellent example of the wide distribution which some species of leeches 



