138 BULLETIN 168, UNITED STATES NATIONAL MUSEUM 



Plate 30 

 Jsotoma (Isotoma) eunotabilis: 



340. Left mucro and end of dens, X 2,016. 



341. Left mucro and end of dens, X 1,920. 



342. Right mucro and end of dens, X 1,908. 



343. Dorsal aspect of right mucro, X 2,016. 



344. Dorsal setae of first abdominal segment, X 757. 

 Isotoma {Isotoma) fmitima: 



345. Mucro. From Scherbakov. 

 Isotoma {Isotoma) minor: 



346. Sense organ of third antennal segment of right side, X 1,890. 



347. Ventral aspect of right antenna, showing sensory cones and setae, X 



1,200. 



348. Right hind foot, X 1,200. 



349. Left mucro and end of dens, X 1,908. 



350. Right mucro and end of dens, X 1,920. 



351. Right mucro and end of dens, X 1,920. 



352. Spinulate seta from abdomen, X 1,200. 



Plate 31 

 Isotoma {Isotoma) albella: 



353. Left eye patch, X 280. 



354. Eyes and postantennal organ of left side, X 512. 



355. Eyes and postantennal organ of left side, X 512. 



356. Sense organ of third antennal segment of left side, X 1,344. 



357. Left hind foot, X 808. 



358. Last four abdominal segments, X 136. 



359. Left mucro and end of dens, 1,264. 



360. Left mucro, X 1,016. 



361. Dorsal setae of first abdominal segment, X 768. 



Plate 32 

 Isotoma {Isotoma) olivacea: 



362. Typical form, eyes and postantennal organ of left side, X 360. 



363. Sense organ of third antennal segment of right side, X 952. 



364. Right liind foot, X 952. 



365. Left hind foot, X 757. 



366. Left mucro, X 1,192. 



367. Left mucro, X 1,192. 



368. Right mucro, X 1,249. 

 389. Left mucro, X 1,192. 



370. Left aspect of tenaculum, X 735. 



371. Dorsal setae of first abdominal segment, X 360. 

 Isotoma {Isotoma) olivacea negleda: 



372. Eyes and postantennal organ of right side, X 443. 



373. Sense organ of third antennal segment of right side, X 952. 



374. Left hind foot, X 952. 



375. Left mucro and end of dens, X 952. 



Plate 33 

 Isotoma {Isotoma) olivacea grisea: 



376. Left postantennal organ and adjacent eyes, X 407. 



377. Eyes and postantennal organ of left side, X 510. 



378. Sense organ of third antennal segment of left side, X 653. 



379. Left fore foot, X 653. 



380. Left mucro and end of dens, X 1,067. 



