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). 

 * Trans. Liverp. Biol. Soc. xiii. 90, 91, 92 (1899). 



6 Op. cit. vii. 113, 114 (1893). 8 See flirther in Hist, of Crustacea, 307, 310. 



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