1950] 
Wray — Nearctic Collembola 
99 
almost touching, distally segments become conical. Mouthparts 
reduced. Unguis unarmed. Unguiculus present. Furcula shorter 
than antennae; manubrium slightly longer than dens, which is 
slightly longer than mucro. Anal horns 2. Integument finely 
granulated. Body short, thick, length up to 1 mm. 
Xenyllodes armatus Axelson 1903. 
(Figs. 26-30) 
This form from Raleigh, N. C., collected from leaf mould has 
been referred to this species as it agrees very well fn most essential 
characters with the description given by Axelson (1912), and also 
with that by Dr. Jan Stach (1949). However, it does vary in some 
characters, such as the length of the anal horns, postantennal organ, 
and furcula measurements, from the illustrations given by Axelson. 
This is probably the first time this genus has been recorded as oc- 
curring in North America. The form from here has been examined 
by Dr. H. B. Mills, Illinois Natural History Survey, and credit is 
given him as first recognizing this form as occurring in North Amer- 
ica as he states that he found it in Montana, previously to the ones 
I sent from this locality. As far as we are aware this genus has not 
been in North American literature as yet. Dr. Jan Stach (1949) 
states that till now this species is only known from Europe. Thus, 
this is an interesting extension of the range of this genus and as 
with other genera, when more intensive collecting is done, one may 
expect or not be surprised to find an ever widening geographical 
distribution. 
Description of North Carolina form. Eyes 5 (Fig. 26) on each 
side of head, equal in size on a dark eyepatch. Postantennal organ 
consisting of a single, trilobed tubercle with a round “central 
organ”; situated in a depression close to front of the eye complex 
(Fig. 26). Antennae with broad basal segments, almost touching, 
distally segments become conical (Fig. 27) ; shorter than head, rela- 
tive lengths of segments as: 3:5:5:8. Fourth antennal segment with 
a rounded lobe at tip, and with 5 or 6 olfactory hairs. Mouthparts 
reduced. Unguis (Fig. 28) unarmed. Unguiculus present but weakly 
developed, small, spinnate. Furcula well developed, shorter than 
antennae; manubrium slightly longer than dens, which is slightly 
longer than mucro (Fig. 30). Anal horns 2, very small but well 
developed (Fig. 29). Integument finely granulate. Clothing of 
