APTERYGOTA 93 



Isotoma palustris var. unicolor TULLBERG, Ofv. k. vet. Akad. fb'rh., xxvm, 



no. i, p. 151, 1871. 



Isotoma palustris var. annulata TULLBERG, ibid. 

 Isotoma palustris var. viridis TULLBERG, K. sven. vet. akad. hand., x, no. 



10, p. 46, taf. 9, figs. 1-8, 1 872 (Sweden, Spitzbergen, Bering Id.). UZEL, 



Sitzber. k. boh. Gesell. Wiss., n, p. 63, 1891 (Bohemia). 

 Isotoma palustris var. fusca TULLBERG, K. sven. vet. Akad. hand. , x, no. 



10, p. 46, taf. 9, figs. 1-8, 1872. UZEL, Sitzber. k. boh. Gesell. Wiss., 



n, p. 63, 1891. 

 Isotoma Belfragei PACKARD, Fifth Rep. Trust. Peab. Acad., pp. 33-34, 1873 



(Texas). MACGILLIVRAY, Can. Ent., xxm, p. 273, 1891. 

 Isotoma tricolor (in part) PACKARD, Fifth Rep. Trust. Peab. Acad., p. 34, 



1873 (Mass.). MACGILLIVRAY, Can. Ent., xxm, p. 274, 1891 (D. C.). 

 Isotoma purpurascens PACKARD, Fifth Rep. Trust. Peab. Acad., pp. 34-35, 



1873 (Texas). MACGILLIVRAY, Can. Ent., xxm, p. 274, 1891. 

 Isotoma plumbea PACKARD, Fifth Rep. Trust. Peab. Acad., p. 35, 1873 (Mass.). 



MACGILLIVRAY, Can. Ent., xxin, p. 274, 1891 ( L. I., Ohio). 

 Isotoma palustris TULLBERG, Ofv. k. vet. akad. forh., xxxm, no. 5, pp. 34- 



35, 1876 (Siberia). 



Alcoholic specimens are either dark green with pale green legs 

 and furcula, or are dark brown. Dorsum marked (fig. 4) with pale 

 round and oval spots, most numerous on meso- and metanotum. Eyes 

 as in figure 40 (var. arctica), eight on either side. Postantennal 

 organs ovate to oval. Antennae half as long again as the head ; seg- 

 ments in relative lengths as 4:6:6:7. Body cylindrical ; segments 

 related as 4 : 10 : 9 : 7 : 8 : 10 : 9 : 4 : 2. Superior claws (fig. 41, var. 

 arctica) long, slender, tapering, slightly curving, laterally pseudony- 

 chiate, inner margin bidentate ; inferior claws less than half as long, 

 parallel sided, acute, apically curving ; tenent hair unknobbed. Fur- 

 cula half as long as the body ; dentes nearly three times the manu- 

 brium in length ; mucrones (fig. 42, arctica) subequally tridentate ; 

 teeth large, blunt, apical tooth falcate, second and third subfalcate and 

 opposite each other. Clothing of dense short curving setae, with long 

 barbellate hairs on the posterior part of the abdomen. Length 6 mm. 



Three individuals, St. Paul Id., 1897; three, Popof Id., 1899 (No. 

 96). 



These agree in every essential respect with European examples of 

 /. viridis, forma principalis, received from Dr. Schaffer and also 

 with specimens collected by myself in Massachusetts, Ohio and 

 Illinois ; the Alaskan forms differ from any which I have seen, how- 

 ever, by being larger and in having no tooth on the inferior claw, 

 with the exception of a single small specimen, 2 mm. long. 



It is not surprising to meet /. viridis from Alaska, as the species 

 has repeatedly been recorded from the Arctic regions and ranges 

 throughout Europe and the United States. 



