526 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



Limnaa diaphana King, Strebel, Zool. Jahrb., XXV, p. 163, Taf. 8, figs. 



looa-c, 1907. 



Limntza lebruni M.ab\[\e, Bull. Soc. Philomathique de Paris (7), VIII, p. 44, 

 1883. Mabille et Rochebrune, Mission Scientifique du Cap Horn, 

 Mollusques, p. 19, 1889. 



Freshwater ponds in the neighborhood of Cape Gregory (Cabo San 

 Gregorio) on the north side of the Straits of Magellan, just west of the 

 4Oth meridian (King). Punta Arenas and Gente Grande, Lagune 

 (Strebel). Punta Arenas (Mabille, for L. lebruni]. 



King's type measured about 17 X 7.5 mm. ; Strebel's shells were smaller, 

 10-13 mm. long, and he seems to have entertained some doubt of their 

 identity with King's. L. lebruni is described as 16 to 20 mm. long, and 

 agrees well with L. diaphana in other respects. It may be noted that 

 Mabille and Rochebrune do not mention L. diaphana, and evidently 

 overlooked it. 



On the Rio Chico de la Santa Cruz Mr. Hatcher collected numerous 

 Lymnaeas of the L. diaphana type, some agreeing with the typical form 

 from the Straits of Magellan, others divergent therefrom. 



In what I take to be typical L. diaphana, from a spring on the Rio 

 Chico, 15 miles above the Sierra Oveja (PI. XLVI, figs. 3, 7, 9) the 

 shell is thin, but moderately strong, narrowly rimate, rather long, the last 

 whorl swollen, but much smaller than in L. d. inelegans, very evenly 

 rounded, with sculpture of unequal growth-lines, but not malleated, and 

 very glossy. The spire is long, slender and acuminate. The shortly 

 ovate aperture is rather small ; columella very narrowly revolute, not 

 adnate above, continuing free to the parietal wall above the axial crevice. 

 The color is light brown, or, when the cuticle is worn off, pink, or pinkish 

 white. Specimens measure : 



Fig. 3. Length 17, diam. 9.4, length of aperture 8.8 mm.; whorls 



" 9- " H " 7-25, ." 6.9 " " 



" 7. " 6.3 mm.; whorls 4 (young shell). 



" 21.2, diam. 11, length of aperture 10.8 mm.; whorls 6. 

 17 " 9.8 " 9.4 " " S 1 A- 



17.8 " 10.4 " " 10 " " 



In a small stream, 5 miles above Sierra Oveja, the shells are nearly 

 typical in shape, but small and thin. One measures, length u.8, diam. 



