NO. 4 schmitt: stomatopods 163 



In S. rugosa a prelateral lobe or angle is not even indicated ; in han- 

 cocki, although blunt, it is well marked. On either side of the median 

 crest of the telson of the former there is a low, but well-defined, convex, 

 bowed-out carina paralleled by a row of longitudinally elongated tuber- 

 cles ; in S. hancocki, instead of a carina and one parallel row of tubercles, 

 there are 2 rows of tubercles paralleling each other either side of the 

 median carina. The 5th submedian carinae of the abdomen are not spined 

 posteriorly in S. hancocki; in S. rugosa they are well spined ; otherwise, 

 the carinae of the abdomen seem to be spined alike. The type of S. rugosa, 

 between the submedian and intermediate carinae of the 5th and 6th 

 abdominal somites, has the posterior margin of these somites armed with 

 a series of spinules; on the 6th somite, 3 on either side, in the greater 

 interspace between the more medially placed 2 of these spinules is a low, 

 tiny, inconspicuous "button" or bead indicative perhaps of a potential 4th 

 spinule; on the 5th somite there are 4 spinules on the left side and 3 on 

 the right; these spinules are placed nearer their respective intermediate 

 carinae than the submedians; to the outside of each of these groups of 

 spinules on the posterior margin of the 5th somite there is a small, low, 

 spiniform denticle, an incipient spinule. There are no such marginal 

 spinules in S. hancocki. 



The intermediate carinae of the carapace which run to or just about 

 to the anterior margin in S. hancocki fall well short of it in S. rugosa. 



The lateral spine or process of the 5th thoracic somite appears to have 

 a slightly backward trend in S. rugosa, inasmuch as the anterior margin 

 is longer than the posterior beyond the angulations that give this process 

 its somewhat lance-shaped form, while the spines into which the lateral 

 margins of the 6th and 7th somites are drawn out point almost directly 

 backward; in S. hancocki the lateral spine of the 5th somite is directed 

 laterally and only slightly inclined or curved forward ; the posterolateral 

 angles of the 6th and 7th thoracic somites, although forming an acute 

 angle, are less sharply and attenuatedly spinelike; moreover, the apices 

 of the broader and more flattened lateral spines are directed more or less 

 sideways and with no particular posterior inclination. 



