JOURNAL OF ENTOMOLOGY AND ZOOLOGY 149 



long and but little curved, second and third teeth of about the 

 same length, vertical, on opposite sides of the mucrones and 

 nearl}' opposite each other. 



Variation: MacGillivray described the antennte, "First and 

 second seginents dihited, as liroad as long and twice as broad 

 as the third and fourth." In my specimens I is as broad as 

 long, but this is not true of II. Also I and II are not as broad 

 as III and IV. 



Habitat: A very few of these s]iecimens were found under 

 the rocks during low tide at Laguna Beach. 



C. B. Davenport has collected specimens from the sand at 

 Cold Spring Beach, Massachusetts, and they have been taken 

 from Spitzbergen, Polaris Bay, and Massachusetts Bay. 



Isotoma aspera n. sp. 

 (Plate II, Figs. 1-4) 



Description: Length — 1.5 mm. Color — Great variation, dirty 

 white with no markings to mottled gray. Antenna^ — Longer than 

 head, IV longest and thickest, II and III subequal, I little shorter 

 than II and III. Ocelli — "Widely separated, sixteen. Postan- 

 tennal organ — Ellijitical with a rim. Claws — Two ; superior 

 armed with two teeth on the inner margin, and two teeth on 

 the outer margin; inferior, wide and stout, curved on the inner 

 margin. Furcula — Does not reach ventral tube; dentes nearly 

 three times manubrium; mucrones short and curving, triden- 

 ticulate, second and third teeth opposite. Integument — Very 

 hairy. 



Variation: The color varies a great deal. 



Habitat: Camp Baldy, altitude 4700 feet, March. Lytle 

 Creek, April ; San Dimas, left fork. 



Isotoma »iini)))a Guthrie 

 (Plate II, Fig. 5) 

 Isotnwa minima Guthrie, 1903. The Collembola of Minnesota, 

 Geol. and nat. hist. surv. of Miim. zool., series 4, pp. 1-110. 

 Description: Length — .75 mm. Color — Grayish blue. An- 

 tenna? — Short, little longer than head; IV longest and swollen; 



