MOORE: HIRUDINEA OF SOUTHERN PATAGONIA. 675 



Semiscolex variabilis appears to be a small leech. Blanchard's speci- 

 mens varied from 10 to 37 mm. in length. The smallest example here 

 described measures 8 mm., the largest, which is poorly preserved, about 

 23 mm., and the individual which furnished most of these notes and is 

 represented of natural size in fig. i has the following measurements. 



Length, 2 1 mm. 



Anterior end to male pore, 6.5 mm. 



Width at male pore, 2. i mm. 



Greatest width (XX), 3.6 mm. 



Diameter of posterior sucker, 1.3 mm. 



Depth at male pore (about), .8 mm. 



Greatest depth (about), 1.4 mm. 



Two specimens come from a "large spring 30 miles above Sierra Oveja, 

 Rio Chico, Feb., 1899," Station 22 ; the third is from a " drying-up pool 

 near Arroyo Eke, Alt. 2100 ft., Feb., 1899," Station 43. 



GLOSSIPHONIA DUPLICATA sp. nov. 



(Plates XLIX, Fig. 10; L, Figs. 16-22.) 



This species resembles G. (Helobdelld] scutifera R. Blanchard, but is 

 readily distinguished by the distinctly double annuli, the form of the 

 nuchal plate, the metameric color pattern, etc. 



Without exception all of the very large number of preserved specimens 

 are stout and thick, less wide and flattened, but much deeper and more 

 strongly convex dorsally than examples of G. sctitifera preserved in the 

 same bottles. The anterior end is somewhat slender, the posterior 

 broadly rounded, the greatest width being at about the beginning of the 

 posterior third. The anterior sucker is small, with a contracted opening 

 and thick margin ; the prostomium prominent. In almost all of the 

 specimens a low elevation arises from the middle of the sucker, with a 

 deep groove bounding it anteriorly. The mouth is rather large, situated 

 in a thickening which represents the ventral portion of somite III, and is 

 the center of several radiating furrows (Plate L, fig. 18). 



The contracted, thick-rimmed posterior sucker is so strongly directed 

 ventrad that it is entirely concealed from above (Plate L, figs. 19 and 20). 



Following are the measurements of the type specimen, than which 

 some examples are several millimeters longer, as well as relatively deeper. 



