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lembolen gesammelt von der schwedischen Siidpolarexpedition,” 
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DESCRIPTION OF PLATES. 
Plate I. 
Fig. 1. Isotoma Brucei , side view, x 40. 
Fig. 2. Do. left side of head, dorsal view, showing ocelli, 
feeler, antennal organ (a. of and post-antennal organ (p. a. o.), 
x 100. 
Fig. 3. Do. right mandible, ventral view, x 200 ; ap., apical 
teeth ; mo., grinding surface. 
Fig. 4. Do. right maxilla ( mx .), ventral view, shown in as- 
sociation with the tongue (tin.), and the right maxillula (mxl.) ; 
ga., galea ; la! , ventral lamella ; la.”, inner lamella ; sti., stipes ; 
car., cardo ; pa., palp ; pd., foot of tongue ; lig., ligament of tongue. 
The left maxilla and the left half of the tongue are removed to 
expose the left maxillula (mxl!), and its supporting arm, hr., x 200. 
Fig. 5. Do. hindmost leg, showing claws, x 200. 
Fig. 6. Do. dorsal view of spring, x 200. 
Fig. 7. Do. dens and mucro of spring, side view, x 250. 
Fig. 8. Do. retinaculum, side view, x 600. 
Plate II. 
Fig. 9. Isotoma octo-oculata , var. gracilis, side view, x 40. 
Fig. 10. Do. left corner of head, showing ocelli, post- 
antennal organ (p. a. o.), feeler, and antennal organ (a. o .), x 100. 
Fig. 11. Do. hindmost foot, with claws, x 200. 
Fig. 12. Do. tip of dens with mucro, side view, x 300. 
Fig. 13. Cryptopygus crassus, young specimen, x 40. 
Fig. 14. Do. adult female, side view, x 40. 
