66 G. M. Giles— On the Structure and [No. 1, 



Cyrtofhium calamicola, n. sp. 



Length 3 — 5 mm. 



Colour a golden brown plentifully mottled with deep chocolate 

 coloured blotches. 



Head subquadrate with a slight beak-like prominence in the 

 middle line. Antennules hairy, as long as the head and the first five 

 segments of the thorax together; their peduncles subequally three- 

 jointed, flagellum (in largest specimens) consisting of six joints, 

 the last joint claw-shaped ; length of flagellum to peduncle as 3 : 8. 

 Antennae hairy, generally equal to the antennules in length ; the 

 peduncle four-jointed, coxocerite very short, fourth joint slightly longer 

 than the third ; number of flagellar joints equal to that of the superior 

 antennae ; length of flagellum to peduncle as 5 : 12. The number 

 of joints in flagella of both superior and inferior antennae varies con- 

 siderably : I have met with instances of 3, 4, 5, 6 ; the joints appear 

 to be always equal. 



Thorax. 4th, 5th, and 6th somites of nearly equal length and 

 longer than those before and behind them ; 1st the shortest of all. 

 Coxal plates increase in size from before backwards ; those of the 

 gnathopoda very small, and, with those of the two following appendages, 

 not long enough to overlap ; the posterior three considerably larger, 

 imbricate. 2nd pair of appendages, or anterior gnathopoda, consi- 

 derably less robust than the posterior ; propodite long, ovate ; dacty- 

 lopodite as long as the propodite, its concave border very finely serrate ; 

 carpopodite triangular, its articulation with the meropodite so oblique 

 as to coincide nearly with the long axis of the appendage. 3rd pair of 

 appendages, or posterior gnathopoda, very large ; dactylopodite as long 

 as the propodite, provided with a peculiar serrature of square, chisel- 

 edged teeth ; propodite long, ovate ; carpopodite triangular, its postero- 

 inf erior angle produced into a strong tooth with a smaller, less acute 

 tooth close to the posterior border of its articulation with the propodite ; 

 articulation of carpopodite with meropodite as in the 1st gnathopod. 

 4th and 5th pairs of appendages alike in form, with claw-shaped dac- 

 tylopodite ; the latter is, however, much the more robust. 6th pair of 

 appendages differing a good deal from the others ; the posterior border of 

 their dactylopodite provided with two curious short finger-like processes. 

 7th and 8th pairs of appendages alike in general form, the 7th slightly 

 smaller than the 8th, their basipodites having the posterior border 

 strengthened by a lamellar buttress-like expansion ; dactylopodite round- 

 ed and provided with a large tuft of hairs ; both these appendages are 

 habitually kept extended backwards in the long axis of the body. 



Abdomen. Anterior three appendages of the usual swimmeret type } 



