430 Rey. A. M. Norman on an undescribed 
Abdomen a thorace ad caudam gradatim diminuens. Appendia 
antennarum squamiformis oblongo-lanceolata, apice oblique trun- 
cato, spina ad marginis exterioris apicem munita; apex margoque 
interior dense ciliati; margo exterior sine ciliis. Thoracis frons 
rostrata ; rostrum breve, obtusum, vix tertiam oculorum partem 
superans. Oculi appendicis antennarum tertiam partem vix eequant. 
Antenne prelonge. Telson (sive lamella caudalis media) apice 
fisso intermedias fere pervenit lamellas ; fissura brevis. 
Colour very variable, whitish, ashy, green or brown of various 
shades. Carapace cylindrical. Rostrum short, triangular, not 
exceeding one-third the length of the eye-peduncle. Antennal 
scale oblong-lanceolate, with an obliquely truncate apex, three 
times the length of the eye, and more than twice that of the 
peduncle of the internal antennz; a spine at the apex of the 
outer margin, which is not ciliated; inner margin and apex 
densely ciliated. Antenne long and slender. Telson about as 
long as the intermediate laminz, bifurcate about one-third of 
its length. 
The most widely diffused species on our coasts; common in 
rock-pools. 
Mysis Lamorne, R. Q. Couch. PI. VIII. figs. 4 & 5. 
Mysis Lamorne, Couch, The Zoologist (1856), p. 5286; White, Pop. Hist. 
Brit. Crust. p. 143. 
Mysis crassus, sanguineus vel aurantius. Thoracis latera pone 
multum dilatata. -4édomen lateribus fere parallelis, segmentisque 
subsequalibus. Appendix antennarum squamiformis obovyata, 
brevis, utrinque dense ciliata, nulla spina instructa. Thoracis frons 
breviter rostrata. Pedunculi oculorum perbreves, attamen appen- 
dicis antennarum brevis plus quam dimidium superantes. Antenne 
prelonge. Telson breve, ad apicem atque per longitudinis tertiam 
partem fissum, intermediarum dimidium lamellarum tantum attingit. 
Colour “arterial-blood-red” or orange. Carapace greatly 
widening behind, and “more enlarged posteriorly than in any 
other long-tailed Crustacean” (Couch). Abdomen of nearly equal 
diameter throughout. Rostrum short, triangular, one-third the 
length of the very short peduncle of the eye. Antennal scale 
ovate, with the apex rounded, very short, slightly exceeding the 
length of the peduncle of the internal antennz, ciliated all 
round, and having no spine on the external margin. Antenne 
long. Telson short, half the length of the intermediate lamine, 
the bifurcation through half its length. 
This species approaches very near to M. oculatus O. Fab. 
(Cancer oculatus, O. Fab. Faun. Green. p. 245; Mysis Fabricii, 
Leach, Linn. Trans. vol. xi. p. 350 ; Thompson, Zool. Researches, 
Part 1), and may prove to be synonymous with it. 
Rock-pools: Penzance (Couch) ; Falmouth (Norman). 
