298 DE. J. Q. DE MAN ON THE PODOPHTHALMOTJS 



aljdomen presents on each side two linear impressions close and 

 parallel to the lateral margins, which are confluent posteriorly. 

 A trace of such an impressed line is found on the fourth seg- 

 ment, but the five anterior postabdominal segments have their 

 upper surfaces perfectly smooth. The postero -lateral angles of 

 the three anterior postabdominal segments are rounded and 

 obtuse, but those of the fourth and fifth segments terminate 

 in an acute spinule. The sixth segment is armed, as usual, 

 with six, longitudinal, very acute spines ; those which constitute 

 the postero-lateral angles are the longest, extending most back- 

 wards. The distance between the two submedian spines is 

 less than that of the next spine from each of them, and even 

 a little less than the distance between the two lateral spines. 

 The terminal segment is transverse, being much broader than 

 long and about as long as the preceding segment. In its arma- 

 ture this segment much resembles that of the other species of 

 the genus JPseudosquilla and appears even to be similar to Pseu- 

 dosgidlla Lessonii. The posterior margin is armed with six 

 acute spines, of which the two submedian are mobile and well 

 developed ; they are placed close to one another, and no teeth 

 are observed between them. Between the submedian spines 

 and the first lateral ones I observe two small truncate teeth, 

 and a similar small truncate tooth occurs between the first and 

 the second lateral spines. 



The upper surface of the segment presents a compressed, ele- 

 vated, longitudinal, median keel, terminating posteriorly in an 

 acute spine ; on each side of the median keel five longitudinal 

 carinse are observed (the keeled lateral margin being "included), 

 of which the first and the third, however, are interrupted, the 

 others being continuous. The first, situated next to the median 

 keel, consists, more properly, of a longitudinal row of three 

 acute spines (that of the left side presenting only, two spines); 

 the second lateral carina is continuous, but terminates posteriorly 

 in two small acute spinules, placed one behind the other. The 

 third lateral keel is again interrupted in the middle, the pos- 

 terior portion terminating in an acute spinule ; the fourth 

 lateral keel is continuous, and proceeds upon the external lateral 

 spine of the posterior margiu even to its point. The under 

 surface of the terminal segment is armed with four acute spines, 

 two on each side, corresponding with the interstices between 

 the spines of the posterior margin. 



