53° 
The Ohio Naturalist. 
[Vol. VI, No. 7, 
Thorax, .31 mm. long, .47 mm. wide; greatly constricted at middle. 
Prothorax twice as broad as long, much narrower than head; anterior 
angle rounded, two small hairs with bristle between, two more bristles 
near posterior angle, several small bristles along posterior border; a nar- 
row transverse band one-third of the way from front, with longitudinal 
bands near each end, diverging bands running half-way to front from 
])osterior border. Metathorax shorter and broader than prothorax with 
straight diverging sides, also nearly straight anterior and posterior su- 
tures; two long bristles at posterior angle, twelve long hairs along posterior 
border; a little darker than prothora.x. Legs rather large especially the 
fennir, and fulvous. 
Abdomen with sides and posterior evenly rounded, wide transverse 
bands extending from side to side, sutures curved except last one; invag- 
inations in the chitin of the lateral margins of all the segments except 
the last two produce clear notch-like spaces; one large and one small bristle 
at posterior angles of all but terminal segment; numerous long hairs on 
posterior borders of segments ; fringe of fine hairs along sub-margin of last 
segment; last three sutures marked by clear spaces; first four segments 
have three small hairs on lateral margins. 
Described from specimen in Professor Osborn’s collection, 
taken from Aegialitis vocifera at Ft. Collins, Colo., by R. C. 
Stephenson. 
This work was carried on in the Zoological Laboratory of 
Ohio State University under the direction of Professor Herbert 
Osborn, to whom the writer wishes to express his thanks for val- 
uable assistance. 
KEY TO THE SPECIES OF LIVERWORTS RECOGNIZED 
IN THE SIXTH EDITION OF GRAY’S MANUAL OF 
BOTANY. 
Edo Claassen. 
This key may be considered as a continuation of the one pub- 
lished last year in the Ohio Naturalist (Vol. V, p. 312.) Its pur- 
pose is therefore the same; it is intended to make the study of 
the liverworts and their determination more easy. It was 
thought to be necessary to put into the key more characters than 
are usually given. Rather than hamper the student in any way 
in his efforts to determine the liverworts, this extended key is 
l.)elieved to enable him to overcome the obstacles in his path. 
Am’um Dumort. 
1. Thallus narrow (about 2 mm. wide), palmately and pinnately 
divided or pinnate or bipinnate. 2. 
'I'hallus wider (4 mm. wide or more), simple or irregularly lobcd. 4. 
2. Calyptra smooth, not tuberculate, more or less hairy or squamu- 
lose, obovate-pyriform, about 3 mm. long. pinnatifida Xees. 
Calvptra more or less verrucose or tuberculate. 3. 
3. Thallus biconvex with wide margin, formed by a single layer of 
cells (therefore in transverse section lens-shaped ; calyptra cylin- 
drical, (j-8 mm. long. midtifida Dumort. 
Thallus flat, pellucid, with narrow margin (in transverse section of 
nearly equal thickness or planoconvex); calyptra pyrifonn- 
clavate. latifrons Lindb. 
