6 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 124 



No. 33. Lot No. 480. Cave Rock, Douglas County, Nevada. Depth, 110 to 

 159 feet. Dec. 21, 1963. Ten asexual specimens of Phagocata. Coll. Frantz and 

 Saake. 



No. 34. Lot No. 457. Cave Rock, Douglas County, Nevada. Depth, 245 feet. 

 Oct. 28, 1962. Three asexual specimens and 3 fragments of Phagocata. Coll. 

 Frantz, Curran, and Saake. 



No. 35. Lot No. 448. Cave Rock, Douglas County, Nevada. Depth, 290 to 325 

 feet. July 17, 1962. One, probably not fully mature, specimen of Phagocata. Coll. 

 Frantz, Curran, and Saake. 



No. 36. Lot No. 461. Cave Rock, Douglas County, Nevada. Depth, 299 to 415 

 feet. Dec. 19, 1962. Two asexual specimens and 2 fragments of Phagocata. Coll. 

 Frantz, Curran, and Saake. 



No. 37. Lot No. 482. Cave Rock, Douglas County, Nevada. Depth, 342 to 348 

 feet. Dec. 21, 1963. One sexual (No. 482a: whole mount) and 12 asexual specimens 

 of Phagocata. Coll. Frantz and Saake. 



No. 38. Lot No. 456. Cave Rock, Douglas County, Nevada. Depth, 422 feet. 

 Oct. 28, 1962. Three asexual specimens of Phagocata. Coll. Frantz, Curran, and 

 Saake. 



No. 39. Lot No. 471. Cave Rock (Skyland), Douglas County, Nevada. Depth, 

 438 feet. May 13, 1963. One sexual (No. 471a: whole mount) and 3 asexual speci- 

 mens of Phagocata. Coll. Frantz and Hauswald. 



No. 40. Lot No. 476. Cave Rock, Douglas County, Nevada. Depth, 443 to 449 

 feet. Aug. 20, 1963. Two sexual (476a: slides) and 4 asexual specimens of Phagocata. 

 Coll. Frantz and Zorko. 



Family Planariidae 



Genus Phagocata Leidy, 1847 

 Phagocata nivea tahoena, new subspecies 



Figures 2, 3; Plate 1 



A large number of specimens of this planarian was collected from 

 many stations of Lake Tahoe (see "List of Localities"). 



Description. — The appearance of this subspecies is shown in 

 plate 1a-f. This is a slender, rather small pigmented species. 3 Sexually 

 mature worms in a preserved condition are usually 5 to 8 mm long 

 and 0.7 to 1.0 mm wide (largest specimens measured up to 12 mm in 

 length), with the typical appearance of the genus Phagocata, i.e., 

 with a truncate head without conspicuous auricles. There is no 

 distinct narrowing behind the head. The body then gradually widens, 

 reaching its greatest width at the level of the pharynx and copulatory 

 apparatus. Behind the genital pore the body tapers to the moderately 

 rounded posterior end. 



3 Regarding the color and size of the living specimens of the Lake Tahoe pla- 

 narians, Mr. Ted C. Frantz informed me (in litt.) that "color varied from dark 

 brown to translucent pink. The 'pink' were few in number and inhabited the 

 bottom depth of the lake. They were also the largest of the planarians and ap- 

 proximately one-half inch or so in length." I consider his "dark brown" specimens 

 to be Phagocata nivea tahoena and the "large translucent pink" specimens to be 

 Dendrocoelopsis hymanae, described as a new species later in this paper. 





