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 A HISTORY OF LANCASHIRE H. varians. Hippolyte cranchii and Hippolyte pusiola (Kroyer), less common, but occurring with the foregoing. A species of Mysis which gave interesting results and which occurs with Hippolyte has been determined as Mysis neglecta (G. O. Sars).' ' These three or four species are too small to be of any direct commercial importance. The tufts of hair on the body of H. fascigera, to which the specific name alludes, are easily detached, and when a specimen becomes bald there is apparently nothing left to distinguish it from H. varians.^ On the other hand there are weightier characters which may justify the assignment of the two remaining species to a separate genus. Hippolyte, in the restricted sense, has a proper cutting edge to the mandible, but no palp, and the fifth joint or ' wrist ' in its second pair of legs is subdivided into only three pieces or subarticulations. In contrast to this the genus Spirontocaris (Bate) has a palp to the mandible, but the cutting edge is rudimentary, and in the second pair of legs the ' wrist ' is seven-jointed. It is with these latter conditions that H. cranchii and H. pusiola appear to comply, so that they should rather stand under the generic name Spirontocaris^ The occurrence of Mysis neglecta introduces us to the sub-order Schizopoda, or cleft-footed Malacostraca. They derive their name from a feature which is not exclusively theirs, since trunk-legs with two branches are to be found in all the malacostracan sub-orders. The family Mysidae is in one respect very peculiar, inasmuch as the members of it have no true branchis. Mr. Andrew Scott, in his observations on the habits and food of young fishes, says that plaice and flounders ranging from two-fifths to three-fifths of an inch in length make their diet almost entirely of Copepoda, but later on the stomachs of the smaller flat fishes ' from one inch up to four inches in length, captured on the shores of our neighbourhood, are usually almost entirely filled with Mysis,' and the young of many round fishes also feed on the same little shrimp.* For Mysis neglecta the name Praunus neglectus is to be preferred. Leaving the stalk-eyed Malacostraca we now pass on to the sessile-eyed division, containing three sub-orders, the Sympoda, Isopoda, and Amphipoda. The Sympoda, formerly called Cumacea, have characters which connect them pretty closely with the preceding podophthalmous division. In examining the food found in the various fishes Mr. A. O. Walker was able to identify Pseudocuma longicorne (Bate), sometimes called P. cercaria (van Beneden), from plaice and pogge taken at Morecambe, and Diastylis rathkii (Kroyer) from solenette at Blackpool.* The former of these species belongs to the family Pseudocumids, in which the terminal tail-piece or telson is distinct, but small and unarmed. The other species belongs to the family Diastylidas, which have a well-developed telson ending in two spines.* The Isopoda of the county have not yet found a collector with the enthusiasm which any thorough and effective knowledge of this sub-order imperiously demands. They differ from all the rest of the Malacostraca that have been here mentioned by the position of the breathing organs. These in the genuine Isopoda are supplied by the pleopods, appendages of the pleon or tail, instead of being connected (as in almost all the other groups) with ' Tram. L'wetp. Biol. Soc. xiii. 150, 152, 153 (1899). 2 A. O. Walker, ^ra. Nat. Hist. Ser. 7, vol. iii. 147 (1899). ' Stebbing, Hist, of Crustacea, Internal. Scientific Ser. Ixxiv. 234, 236 (1893). 6 Op. cit. vii. 113, 114 (1893). 8 See flirther in Hist, of Crustacea, 307, 310. 164
 * Trans. Liverp. Biol. Soc. xiii. 90, 91, 92 (1899).