PAMrilll.lDI: TllK CKXCS KHYXXIS. 1637 



apical expansion, the whole less than half as Ion;: as tho seijnients, erect, excepting an 

 uppermost row. in wliich they arc iiiclinedlnwards ; they are arraufteil on each sef;ment 

 as follows: a subdorsal series, placed one in the middle of tlie anterior half ; a lateral 

 series, one in tlie middle of tlie posterior lialf ; a suprivstiginatal series, one a little in 

 front of the middle: and an iufrastisnaatal series, one anterior and one posterior; 

 claws of proleirs arranged in oblii|ue ovals. 



Mature caterpillar. Head full, well rounded, broadest below and well arched 

 above, the median suture but little sulcate ; viewed laterally tlie head is of nearly equal 

 depth on the lower half, gradually and sliglitly narrowing above, where it is also well 

 ronnded: triangle twice as higli as broad, scarcely tapering in the lower half, its 

 apex reaching consideral)ly al)ove tlie middle of tlie head. Head uniformly vermiculatc 

 throughout, and covered with very short, delicate pile. Second joint of antennae 

 small, roundish ; third but little slenderer, cylindrical, slightly larger at tip than at 

 base, more than twice as long as broad ; fourth very minute, similar in form to third. 

 Ocelli six in number, five of tliem placed in a regularly but strongly curved series, its 

 convexity downward and forward, the second and third counting from above in con- 

 tignity, the first distant from the third slightly more than the fourth from the third or 

 fifth, the last opposite the base of the antennae, and at an equal distance from it and 

 the fourth ocellus ; sixth nearly on a line with the fifth and the antenna, and nearer to 

 it than to any of the others; all the ocelli of nearly equal size, not very prominent, the 

 upper quite flat. Labruiu very sm.all, more than twice as broad as long, but slightly 

 and broadly excised in the middle of the front, which othenvise is well rounded. 

 Mandibles pretty large and very stout and heavy. Labial palpi small, the joints of 

 nearly equal length, and decreasing rapidly and regularly in stoutness. Si)inueret 

 small. 



Body moderately plump, cylindrical, but tapering from the middle forwards, the 

 second thoracic segment about as large as the head, the posterior half at least of each 

 segment tr.ansversely wrinkled and the whole body covered with minute, raised 

 points, irreguliirly distributed, ami an infrastigmatal series of niinnte, crateriform 

 disks, situated centrally on the first to eighth abdominal segments, and a similar 

 laterostigmatal disk on the middle of the third thoivacic segment, looking like a false 

 spiracle; first thoracic segment with a rather slender, transverse, corneous shield, 

 nearly uniting the front of the spiracles, scarcely parted at the dorsal line. Spiracles 

 very small, the edge heavily ridged, obovate, twice as high as long, that of the first 

 thoracic segment four times as large as the others. Legs rather short, slender, taper- 

 ing, compressed, pretty heavily clothed beneath with short bristles ; the claw small 

 and slender; prologs of moderate size, short, tapering rapidly, and armed with very 

 small hooks. 



This genus, tolerably rich in species, belongs to the north temperate 

 zone and is almost exclusively confined to America, a single species only 

 being found in the Old World. On both continents it extends from ocean 

 to ocean. In the Old World, the single species known, E. comma, is 

 found from Atlantic to Pacific between the 35th to the 60th degree of 

 latitude and extends up the sides of the Alps to the height of 7,000 feet. 

 The northernmost points from which it has been recorded are northern 

 Scandinavia and Finland ; and the southernmost Corsica, Syria and the 

 Altai Mountains in Asia. In the New World, the genus reaches from 

 Lat. 32° to 53° only, and no single species has any such range ; most of 

 them are species of high altitudes ; only one species is common throughout 

 New England ; another is not uncommon in the southeni portion, and 

 the remaining two have in a few instances been found within its limits or 



