. Description of a New Species oj SplCseroma. 107 



.animal was rolled up like a ball." Notwithstanding the close resemblance 

 in habits and appearance of this species, as described and figured, to the 

 present one, there are four jwints of difference : 



I. Till- innnher and ari'ttugt'inent of the tubercles in tJie tiro species.— In S. ras- 

 tutor fonr tubeifles are described on each of the last three segments of the 

 thoi-ax, ami only two are figured on the anterior portion of the pleon. 

 In the species vuider discussion, however, there are four tubercles on the 

 seventh segment of the thorax only and six on the abdomen, two on the 

 post-abdomen, and four on the anterior portion of the caudal shield. 



II. The druclure of the feet. — In <S'. vastator the legs of the first tiiree i^airs 

 are not proportionately as long as those of the present species. The merus 

 is differently shaped, not being cylindrical in that species, and is relatively 

 sliorter. Although Spence Bate mentions no dissimilarity in structure in 

 the legs of the fourth and fifth pairs, still a difference is shown in the cut 

 in the formation of the merus. With our species the difference in these 

 two pairs of legs is merely in proportion. There is a greater resemblance 

 in the sixth and seventh pairs of legs of the two species. 



III. Tlie upcurved margin of the posterior half of tlie tertninal segment if tlie 

 abdomen. 



IV. Tlie presence of numerous tubercles furnisJied witli bristle-like hairs upon 

 the abdomen. 



Neither of these points are mentioned in the description of Sphxroma 

 vastator. 



