8o 



THE yVMERICAN ENTOMOLOGIST. 



made appears to have been much mutilated, and his 

 figure (/. c. V, 751) is very incorrect. The head is 

 represented much too large, and the antennre are 

 reversed in relative position. Prof. Cope de- 

 scribes, from the region of the W3'andotte Cave 

 a drcidotea distinguished from C. stygia by its 

 smaller and more acuminate head (/. c. vi, 411 

 and 419). Apparently the comparison was made 

 only with Packard's figure, if so his species {C. 

 microcephala) is very doubtfully distinct. The 

 external egg-pouches with which its body is made 

 to terminate, are certainly fanciful creations hav- 

 ing no existence in this Isopod crustacean. It 

 is difficult to understand how their number and 

 position could be determined in specimens which 

 " are in bad condition, having lost their limbs, 

 egg-pouches, and the distal portions of their an- 

 tennaj." Packard's specimens had also lost the 

 longer antennae, and neither of these authors 

 mention the existence of caudal stylets. 



The following additions and corrections will 

 aid in the determination of the Mammoth Cave 

 species : 



Inner, short antennae with from nine to twelve 

 joints, the first three subequal, much longer and 

 stouter than the rest, together making nearly half 

 the entire length of the organ ; fourth joint very 

 short, oblique ; fifth joint longer ; the remainder 

 diminishing in length and thickness to the end. 

 The four outer joints bear on the inside a flat-, 

 tened, cultriform spine, terminal joint minute, 

 tipped with a bristle, bearing the cultriform spine 

 upon a projection at the side. Outer antenna3 

 nearly equal to the body in length, with three 

 large basal joints, the first short and stout ; the 

 • second long, together with the first about, equal 

 to the inner antenna; ; the third equal to the two 

 first, and also to the thirteen following ; the re- 

 maining joints closely applied, transverse at first, 

 gradually diminishing towards the tip of antenna;. 

 In six specimens the number of short joints of 

 the outer antennic was found to be, by careful 

 count, respectively Co, 57, 50, 40, 40 and 36. The 

 number of short joints varies also in the inner 

 antennae, and is not always the same in both 

 members of the same pair. The caudal stylets 

 are long, flattened, two-branched ; the longer 

 branch terminal, bent downwards ; the shorter, 

 spindle-shaped, directed outwards from near the 

 apex ; both are tipped with a few bristles. The 

 stylets vary from 3.5""™ to 2. 75"'"^ in length. 

 Measurements of a large number of specimens 

 show great variation in size, the length of the body 

 proper ranging from 4 to 9'"'" and the appendages 

 varying in specimens of the same size. The 

 specimen here figured is of medium size, and 

 gives the following measurements, — length of 

 body 7'"™ = . 28 in., long antennae 6.25""" =.25 in., 

 stylets 3. 5"""*=. 14 in. 



Clustering about the head and base of antenna; 

 in some specimens are seen numbers of minute 

 pear-shaped organisms, covered with hairs, and 

 attached to the surface of the crustacean by thread- 

 like pedicels ; a short tube, or cylindrical pro- 

 jection is sometimes visible near the apex, and 

 the contents appear to be granular with usually 



a large nucleus or vacuole, occupying the lower 

 portion. They were not examined with high 

 magnifying powers, but inay perhaps be stalked, 

 ciliate infusoria. 'Two of these bodies are repre- 

 sented attached to the antenna at Fig. 10, h. 



Adelops hirtiis Tellk. — (Fig. 19, a head of larva 

 from above, li, right antenna from above, c, labium, 

 left maxilla, etc., from below, all much enlarged). 

 The immature forms oi Adelops have never been 

 properly noticed. Packard's figure of the larva 

 (/. c. vol. x, pi. ii.) represents a much contracted 

 specimen, the body tapers too rapidly, and the 

 thoracic segments are nearly one-third too wide, 

 antenna (Fig. 4, a, of his plate) is incorrectl}' drawn. 



The following description made from numerous 

 well preserved specimens, is an attempt to give 

 this larva the careful attention its importance 

 deserves : 



The body is stout and cylindrical, gradual!)' 

 tapering from the thorax, slightly compressed 

 above, dorsal shields covering the segments, very 

 thin and transparent. Color dull white, with the 

 head darker, and tips of mandibles alone tes- 

 taceous. Length 4.4'"'"=. 17 in. Head free, 

 nearly as wide as prothorax, rounded, convex, 

 [Fig. 



Adeloi'S hirtus : a, head of larv.-i from aljove ; />, : 

 c, underside of head (after Hubbard). 



broader than long, sides slightly rounded, trun- 

 cate in front, sparsely covered with fine hairs. 

 No ocelli. Antennae arising from the convex 

 sides of the head, just before the middle, directed 

 backwards ; of four joints, the first tuberculous, 

 the second elongate-cylindrical, slightl}' enlarged 

 anteriorl3^ the third twice as long as the second, 

 slightly curved, thickened on the inner (anterior) 

 side, sparsel}' covered with bristles, a longer 

 bristle on the inside at the thickest portion, a 

 stout spine on the inside at apex, fourth joint 

 appendicuiate, -bearing lateral bristles and a short 

 spine at tip. Epistoma prominent trapezoidal, 

 strongly angulate, edges straight. .Labrum mov- 

 able, deflexed, transverse, oval, bearing spines 

 above and below. Mandibles stout, lobed at 

 base, with molar surface striate, moderately 

 curved, bidentate at tips, overlapping when 

 •closed. Maxillae large, prominent, passing the 

 mandibles, protuberant and strongly angulate at 

 base, consisting of elongate cardinal and basal 

 pieces, and a p3framidal palpiger, obscurel)' sep- 

 arated into two lobes by a longitudinal furrow, 

 the upper lobe bearing internall}' four or five 

 spines, the lower lobe terminating in a curevd, 

 ciliated crest; maxillary palpus, arising from the 

 base of the palpiger, of two stout basal and one 



