680 PATAGONIAN EXPEDITIONS : ZOOLOGY, 



extends to XXIV inclusive. The intestine has the usual four pairs of 

 lateral caeca in XX to XXIII inclusive, all of which are dorsad of the 

 large gastric caeca. The first three pairs are sacculated, the last smooth. 

 Each of the gastric and intestinal caeca arises directly over the correspond- 

 ing ganglion and, with the exception of the last gastric, is confined to the 

 limits of one somite. 



This species must be exceedingly abundant throughout the region of 

 Mr. Hatcher's explorations, as the following list of the localities and num- 

 ber of specimens will show. 



Station No. 7. "Small running stream south side of Rio Chico, 25 

 miles above Sierra Oveja, Feb., 1899." i specimen. 



Station No. 8. Spring at the same locality. 12 specimens. 



Station No. 11. "Small running stream south side of Rio Chico, 15 

 miles above Sierra Oveja." n specimens. 



Station No. 17. "Small stream running from spring on Rio Chico, 25 

 miles above Sierra Ventana, Feb., 1899." 8 specimens, one of which 

 bears eggs. 



Station No. 25. "Spring on Rio Chico, 15 miles above Sierra Oveja, 

 Feb., 1898." i specimen. 



Station No. 36. "Spring on Rio Chico, 30 miles above Sierra Oveja, 

 Mar., 1898." 24 specimens. 



Station No. 38. " Spring on Rio Chico, 25 miles above Sierra Ven- 

 tana, Mar., 1898." i specimen. 



Station No. 40. " Spring on Rio Chico, 25 miles above Sierra Oveja, 

 Mar., 1898." 6 specimens. 



" In spring on Rio Chico." Six small specimens of 6-8 mm. which 

 show the divided annuli distinctly. 



GLOSSIPHONIA SCUTIFERA (Blanchard). 



The reproductive organs of Glossiphonia (Helobdella] sciitifera are inter- 

 mediate in character between those of G. duplicata and G. michcelseni in 

 that the vas deferens does not abruptly enlarge to form the sperm sac im- 

 mediately after turning caudad, as in the former, nor yet retain its tenuity 

 for several somites further back, as in the latter, but passes first into a 

 region of intermediate diameter before again increasing to the full size of 

 the sperm sac. That these differences are constant, seems certain from 

 the verification of the observation in repeated dissections. The ductus 



