COLLEMBOLA OF THE FAMILY ISOTOMIDAE 139 



381. Left mucro, X 1,067. 



382. Left mucro, X 653. 



383. Left mucro, X 1,120. 

 Isoioma (Isotoma) violacea: 



384. Eyes and postanternal organ of right side, X 393. 



385. Sense organ of third antennal segment of right side, X 1,100. 



386. Left fore foot, X 1,060. 



387. Right mucro, X 1,060. 



388. Dorsal setae of second abdominal segment, X 340. 

 Isotoma (Isoioma) violacea mucronata: 



389. Dorsal setae of second abdominal segment, X 653. 



Plate 34 



Isotoma (Isotoma) violacea mucronata: 



390. Eyes and postantennal organ of left side, X 267. 



391. Fore foot, X 350. Specimen from Alaska. 



392. Left hind foot, X 1,060. Specimen from Greenland. 



393. Left mucro, abnormal in having only 3 teeth, X 1,696. 



394. Left mucro, X 1,696. 



395. Sense organ of third antennal segment of right side, X 847. 



396. Left aspect of tenaculum, X 673. 

 Isotoma (Isotoma) violacea caeruleatra: 



397. Eyes and postantennal organ of right side, X 653. 



398. Left mucro, X 700. 



399. Dorsal aspect of right mucro, X 1,060. 



400. Right hind foot, X 653. 



401. Dorsal aspect of first abdominal segment, X 247. 



Plate 35 



Isotoma (Isotoma) violacea caeruleatra: 



402. Left mucro and end of dens, X 1,192. 



403. Sense organ of third antennal segment of right side, X 1,200. 

 Isotoma (Isotoma) nigrifrons: 



404. Eyes and postantennal organ of right side, X 322. 



405. Postantennal organ and adjacent eyes of right side, X 322. 



406. Sense organ of third antennal segment of right side, X 960. 



407. Left hind foot, X 457. 



408. Left mucro, X 1,200. 



409. Left mucro, X 1,200. 



410. Left mucro, X 1,200. 



411. Left mucro, X 1,200. 

 Isotoma (Isotoma) gelida: 



412. Postantennal organ and adjacent eyes of left side, X 375. 



413. Postantennal organ and adjacent eyes of left side, X 375. 



414. Sense organ of third antennal segment of left side, X 1,200. 



415. Right hind foot, X 457. 



416. Left mucro, X 960. 



417. Left mucro, X 757. 



Pl.^te 36 

 Isotoma (Isotoma) subaequalis: 



418. Postantennal organ and adjacent eye of left side, X 333. 



419. Left hind foot, X 407. 



420. Left mucro and end of dens, X 673. 



421. Left aspect of right mucro and end of dens, X 673. 



