July, 1901] 



PSYCHE. 



221 



and the cylindrical Collembola is par- 

 tially bridi;etl by Ncelus, which, quite 

 unlike Smintiiurus and Papirius, agrees 

 with the Poduridae in respect to the 

 form of the antennae, the articulation 

 and position of the head, and the form 

 of the papillae emitted by the ventral 

 tube. 



The three species of Necliis may be 

 separated as follows : 

 Segmentation pronounced; superior claw 

 untoothed, with a basal pair of subulate- 

 processes {psciidonychiac of Tullberg); 

 dentes untoothed ; mucro sublinear, en- 

 tire ; three pairs of cuticular cupules 

 present, on mesothorax, metathorax and 

 fourth abdominal segments, respectively ; 

 brown; maximum length, 0.25 mm. 



iiiiiiiinus. 

 Segmentation obscure; superior claw 

 unidentate ; dentes toothed or spined ; 

 mucro lanceolate in lateral aspect, and 

 serrate ; cupules absent. 



.Superior claw with a basal pair of 

 linear processes (pseudonychiae) ; in- 

 ferior claw linear-lanceolate ; dentes 

 five-toothed ; ochraceous-buff ; max- 

 imum lengtli, 0.7 mm. . mitri/ius. 

 Superior claw not pseudonychiate ; 

 inferior claw lanceolate or oblong- 

 lanceolate; dentes six-spined ; bluish 

 gray; maximum length 0.56 mm. 



m/'iin/i/s, n. sp. 

 Ncelus miiiutiis I ha\x' fouiul at only 

 one spot, an old pine forest in Arling- 

 ton, Mass., in rich black soil, perenni- 

 ally damp. The species easily escapes 

 ordinary observation on account of its 

 small size and dull color and I took 



only about two dozen examples cltuing 

 four years of continual search. One 

 specimen occurred under the loose bark 

 of a white oak log ; the others were on 

 the under side of dead sticks or else in 

 the soil. Minute white individuals, 

 scarcely discernible, appear early in July ; 

 full grown specimens occur in the mid- 

 dle of that month, are most numerous 

 in mid August and persist, in constantly 

 decreasing numbers, even into Decem- 

 ber, long after the frosts have begun. 



Neelit.-i minutus n. sp. (Plate 2, ligs. 3-1 1). 

 — Genei'al color l)luisli gra\', — the combined 

 elfectof bluish mottliiigs and a pale ground 

 color (lig. 3) ; sternum colored; appendages 

 white, excepting a little color on the bases of 

 the legs of large individuals; the amount of 

 coloration increases with the size, young 

 specimens Ijeing white. Head horizontal, 

 ovate. Eyes and postantennal organs absent. 

 .\ntennae (fig. 4) less than half as long as 

 the head ; ratio of segments, 2: 3: 6: 5; sec- 

 ond segment incrassate. simple or with a 

 ventral lobe; third incrassate; fourth conical. 

 Body oval in dorsal aspect, witli smooth con- 

 tour, showing scarcely a trace of segmenta- 

 tion aljove. Thorax one and one half times 

 as long as tlie abdomen. Claws small ; first 

 and second pairs of superior claws (fig. 5) 

 slight 1\ curved, uniformly tapering, uniden- 

 tate; first pair of inferiors lanceolate, simple, 

 one third as long as the opposed claws; sec- 

 ond pair similar but a little longer; third pair 

 of superior chiws (fig. 6) broad basally, inii- 

 tlentate; thiid pair of inferiors oblong-lance- 

 olate, simple, extending almost as far as the 

 opposite claws ; pseudonychiae absent. Ven- 

 tral tube (figs. 3, 7, S) subclavate with a pos- 

 terior lobe near the base. Manubrium (fig. 9) 

 stout, slightly shorter than the dentes, bifid 

 (fig. 10) ; denies in lateral aspect (fig. 9) cylin- 

 drical, in dorsal view (fig. 10) tapering, with 

 two uiesal .ind four lateral spines; tnucrones 



