48 THE VOYAGE OF H.M.S. CHALLENGER. 



large, widely distributed, transversely banded larva is the young of Lysiosquilla 

 maculata, which is one of the largest and most widely distributed Stomatopods. The 

 value of this identification can be much better estimated after examination of the 

 section on Stomatopod larvae. 



Lysiosquilla {Coronis) excavatrix, n. sp. (PI. X. figs. 8-16). 



Diagnosis. — Body depressed and loosely articulated ; whole dorsal surface smooth. 

 Carapace, with rostrum, making ^^ of the total length from tip of rostrum to 

 tip of telson. Eyes nearly cylindrical, with hemispherical cornese. Scale of second 

 antenna about ^-^ of total length. Eaptorial claw of second maxiUiped oval, with 

 fourteen or fifteen short curved pointed teeth and a much longer terminal tooth on 

 dactylus, and three movable spines on inner side of base of second joint. Second thoracic 

 somite with a blunt rounded lobe on each side. Appendages of third, fourth, and fifth 

 pereiopods ovate, that of the fourth being largest. Sixth abdominal somite with a long 

 acute process on each side, near anterior edge. Telson smooth, nearly rectangular, with 

 one median and two pairs of lateral subacute lobes. Endopodite of sixth abdominal 

 appendage triangular, basal prolongation ending in two simple acute curved spines, the 

 outer much the larger. Larva a long-spined Lysioerichthus. 



General Description. — The carapace is smooth on its dorsal surface, with the gastric 

 sutures distinct from the anterior edge to the transverse cervical suture, behind which no 

 longitudinal sutures are visible. The space included between the gastric sutures is wide 

 and makes up rather more than two-thirds of the total width of the carapace. This 

 is elongated and slightly narrowed anteriorly, with the antero-lateral angles nearly 

 right angles and the postero-lateral angles broadly rounded. The anterior edge of the 

 carapace is nearly transverse, and it is very deeply emarginated on the middle line 

 behind. Its length on the middle line is ^j^, and its greatest breadth about j\fj of the 

 total length. The rostrum is a little longer than wide and the lateral edges are not 

 angulated, but are strongly convex in outline and regularly curved to the base of the 

 short acuminate tip. The rostrum completely covers the ocular somite, and hides the 

 base of the eyes. The first antennary somite ends laterally in long slender acute 

 spines, which curve outwards and forwards. 



The first antennae are very short and their shafts are hidden nearly to the 

 tips below the eyes, which are small, subcylindrical, with terminal hemispherical 

 cornese, and are usually directed forwards side by side. The second antennae are almost 

 as long as the first, and the oval scale is very narrow and short, its length being only 

 ^^00 of the total length of the body. 



The second joint or propodus of the raptorial claw is broad, with an obscure longitu- 

 dinal ridge on its outer surface, and when the dactylus is closed the claw is oval and nearly 



