138 
Walter M. Tattersall. 
near to the L eptomy sinae, from whìch it appears to bave directly 
diverged, along lines of specialisation peculiarly its owd. It does 
not appeal* possible to decide which of the branches of the elongate 
pleopods has become obsolete. 
23. Calyptomma puritani sp. n. 
PI. 7 Fig. 13—18. 
Form generally rather slender, particularly posteriorly; the body 
seems to be roughened by microscopi cai, irregulär, blunt asperities. 
Carapace considerably and evenly vaulted anteriorly, the front 
margin evenly rounded; entirely covering the thoracic segments; 
cervical sulcus well marked; antero-lateral angles rounded. 
Pleon longer than the thorax, rather slender; 1. segment very 
slightly longer than the next 4, which are sub-equal; 6. segment 
very elongate, considerably exceeding twice the length of the prece- 
ding segment. 
Eyes (Fig. 13 and 14) in the form of a contiguous membraneous 
lamella, partly hidden by the vaulted anterior part of the carapace; 
the lamella is completely contiguous and is drawn out anteriorly into 
two pointed possibly tactile, processes; in the part of the lamella 
hidden in dorsal view the optic nerves bave their terminations and 
may be noticed as a dark patch in lateral view (Fig. 14); the optic 
nerves appear to be swollen somewhat at their ends as in Pseu- 
domma^ but I could not detect any ramifications such as are to be 
seen in that genus; the lamella is unarmed with teeth or serrations 
of any kind and seems on the whole to be less rigid than in Pseu- 
domma. 
Antennul ar peduncl e (Fig. 13) rather long and slender; 1. joint 
the longest; 3. joint longer than the second; very feebly armed 
with setae ; no antennular brush of setae was noted in male specimens 
though the latter may be possibly immature. 
Antennal peduncle (Fig. 13) reaching to the distai end of the 2. 
joint of the antennular peduncle; rather more slender than the latter; 
3 joints sub-equal. 
Antennal scale (Fig. 15) about equal in length to its peduncle 
and therefore considerably shorter than the antennular peduncle; 
rather narrow, about 6 times as long broad; outer margin entire 
and terminating in a strong spine beyond which the apex of the 
scale is not produced; there is apparently no spine on the outer 
distai corner of the basai joint. 
