158 Rev. Canon A. M. Norman on British Mysidaj. 



Tlie male lias the last joint of peduncle of antennules 

 furnished with a small densely pilose tubercle, which scarcely 

 reaches beyond the extremity of the joint from which it 

 springs. The pergeopods have the tarsus strongly spined. 

 The pleon has not the epimera produced. The first feet are 

 longer and stouter than the rest, and the terminal joints are 

 furnished with seven curious long strap-formed appendages. 



Hah. Plymouth, a single female, 1890 {A. M. N.). 



Distribution. Naples {A. M. N.) ; Messina and Naples 

 (G. 0. Sars). 



Subfam III. Hetbmomtsinje. 



Genus 4. Heteromysis, S. I. Smith, 1874. 

 sa Chiromysis, G. O. Sars, 1877 (non Heteromysis, Czerniavsky, 1882). 



Body moderately robust. Carapace behind leaving two 

 segments of cephalothorax partially uncovered ;. rostrum 

 scarcely developed. Eyes small, on short stout peduncles. 

 Antennal scale elliptic, small, setose on both margins. First 

 legs quite unlike the rest, very much stouter and also longer ; 

 the propodal joint strong, composed of two articulations, the 

 first long, furnished with spines and sette on inner edge, the 

 second very short j nail well developed. All the following 

 legs are slendei*, the tarsus multiarticulate, ending in a 

 slender setiform claw. Telson cleft at the extremity. Outer 

 nropods setose on both margins, without a second joint. 



Prof. S. I. Smith thus describes the male, which I have 

 not seen : — " Terminal segment of the peduncle of antennule 

 wanting the usual elongated sexual process, but having in its 

 place a very dense tuft of long hairs . . . The appendages 

 of the first five segments of abdomen alike in both sexes ; 

 short and rudimentary, and like the same appendages in the 

 female Mysis ... In life the males are semitranslucent and 

 colourless, while in the females the antennula^, the flagella of 

 the antennae, the ocular peduncles, the thorax with the 

 marsupial pouch, and the articulations of the caudal appen- 

 dages are beautiful rose-colour." 



Heteromysis formosay S. I. Smith. (PI. IX. figs. 6-11.) 



1873. Heteroinysis fo mosa, S. I. Smith, U. S. States Fish and Fisheries 



Comm. Report, 1871-72, p. 553. 

 1879. Heteromysis formosa, S. 1. Smith, " Stalk-eyed Crust. Atlan. 



Coast N. Amer.," Trans. Oonnec. Acad. vol. v. p. 101. 

 1882. Heteromi/sis norvegica, G. 0. Sars, " Oversigt Norges Crustaceer, 



I.," Christ. Videnskab. Forhand. 1882, p. 54, pi. i. figs. 21, 22. 



