Stomatopoda in the Bernice P. Bishop Museum 
By CHARLES Howarp EDMONDSON 
INTRODUCTION 
The Stomatopoda which represent one of the higher orders of 
malacostracous Crustacea constitute a clearly defined group and 
may be recognized by the following characteristics. 
The carapace is relatively small and only partly covers the 
cephalothorax, leaving at least the four posterior thoracic segments 
exposed. The rostrum is separated from the carapace by a dis- 
tinct suture. The abdomen is well developed. ‘The eyes are 
stalked and carried on distinct movable segments, as are also the 
first pair of antennae. The second pair of thoracic appendages 
are developed into raptorial limbs in which the terminal segment, 
called the dactylus, closes upon the preceding one, the manus, 
like a knife blade. Posterior to the raptorial limbs are three pairs 
of thoracic appendages constructed on the same general plan as 
the former but very much smaller. The three posterior thoracic 
segments bear biramous walking legs. Of the seven abdominal 
segments each of the first five bears a pair of appendages, the 
swimmerets, to which are attached tufted gills. The sixth segment 
also bears a pair of appendages, the uropods, which, with the 
seventh segment, the telson, serve as a tail fin. 
All recent Stomatopoda are included in a single family, 
Squillidae, the characteristics of which are the same as those of 
the order. 
In this group relationship between the several genera and also 
between species is based largely upon the peculiar features of the 
sixth and seventh abdominal segments, the raptorial limbs, the 
eyes, and the rostrum. 
Brooks,’ in tracing the generic relationship between the species, 
calls attention to the important significance of the accessory organ 
of the first abdominal appendage of the male stomatopod. 
"Brooks, W. K., Report on the Stomatopoda: Voy. H.M.S. “Challen- 
ger,” Zoology, vol. 16, p. 13, 1886. 
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