SYSTEMATIC REPORT 99 



a short distance beyond the tip of the tooth; peduncle slender, very slightly longer than the antennular 

 peduncle and half as long as the scale (Fig. 18 A, E). Thoracic appendages. As far as can be ascertained 

 without dissection there appears to be nothing unusual in the form of the first and second pairs of 

 thoracic appendages and, unfortunately, the endopods of all the others are missing. The genital organ 

 of the male is already well developed and is of the usual form found in the genus. Uropods slender and 

 shorter than the unusually long telson. In the adult specimen, the endopod is less than three- 

 quarters of the length of the telson excluding the apical spines and the exopods are both broken, so that 



Fig. 18. Pseudomma longicaudum sp.n. A, anterior end of female in dorsal view, x 13; B, immature male in lateral view, x 7; 

 C, antennular peduncle of immature male, x 16; D, process from distal dorsal margin of third segment of antennular peduncle; 

 E, left antenna of immature male, x 16; F, telson and left uropod of adult female, x 13 ; G, telson and right uropod of imma- 

 ture male, x 18. 



it is not possible to tell their length. In the juvenile specimen, the endopod extends almost to the 

 apex of the telson and the exopod extends to the tips of the apical spines, so that probably either the 

 telson becomes proportionally longer as the animal approaches maturity, or the relative lengths of the 

 telson and the uropods differ in the two sexes (Fig. 18 F, G). Telson very long and narrow, nearly 

 twice as long as the last abdominal somite; almost three times as broad at the base as at the apex; 

 lateral margins almost straight and converging evenly towards the apex; armed with many spines 

 arranged in series of larger spines with smaller spines in the spaces between them, extending from the 

 level of the statocyst to the apex. Apex armed with two pairs of long, strong spines and, I think, 

 a pair of median setae. There are no setae present on the apex of either of the specimens, but there 



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