A HISTORY OF ESSEX 



for it belongs to the family Pandalidae. Its proper name is P. montagui, 

 Leach. That which Mr. Lovett speaks of as the true prawn, evidently 

 meaning thereby the prawn most familiar to his own countrymen, is 

 Leander serrafus (Pennant). Its companion species is L. squilla (Linn.), 

 and the third Palezmon above mentioned is now known as Paleemonetes 

 variant (Leach). All these shrimps and prawns are included in a great 

 tribe Caridea, in which the third pair of trunk-legs are simple, that is, 

 they do not end in an opposable thumb and finger forming what is called 

 a chela. This helps to distinguish them, not indeed from all the rest of 

 the Macrura, but from a goodly number, including lobsters and crayfishes 

 and also a large assortment of otherwise prawn-like animals. The tribe 

 is divided into four sections, distinguished by characters of the first and 

 second trunk-legs. Crangon vu/garis and the rest of the first section have 

 the peculiarity that the front limbs are subchelate. They have a finger 

 which is prehensile by closing down upon the extremity of the hand, but 

 that hand is not itself so produced into a thumb as to form a nipper like 

 a pair of tongs. In the next section, which includes Pandalus montagui, 

 the distinguishing feature is in that part of the second pair of limbs 

 which supports the hand. This part, often called the wrist, instead of 

 being as usual a single piece, is here subdivided into several small articu- 

 lations, giving it a snake-like flexibility. The three remaining species 

 all belong to the third section, in which the front limbs may be either 

 simple or chelate, and the second have an undivided wrist. Palamonetes. 

 variant has the advantage of being able to live either in salt water or fresh. 



Of Crangon vu/garis Dr. Sorby notes that it is ' common at all 

 stations especially in the estuaries,' and of Leander serrafus that it is ' very 

 abundant in the open water off the coast but much rarer in the estuaries. 

 The common size is not over three inches but occasionally as much as 

 four.' Of Palinurus vu/garis, the crawfish or rock lobster, he says : ' I 

 have never obtained any in trawling or dredging, but it is caught in traps 

 off Walton-on-Naze.' He further records the little schizopod, Praunus 

 Jiexuosus (Miiller) as ' fairly common in most of the estuaries.' 



Potamobius pallipes (Lereboullet) is not specially assigned to Essex by 

 Mr. Lovett, but in a note to Mr. Lovett's paper Mr. Cole says : ' The 

 crayfish used to be common, and probably is so still, in the Lea and 

 Chelmer, and is found in some of the streams of the New River Company 

 in prodigious abundance.' On the other hand, Mr. Fred Field, writing 

 from St. Leonard's Road, Baling, in March of this year, on the subject 

 of these same freshwater crayfishes, says ' the Colne which used to be full 

 of them no longer contains any.' 



The sessile-eyed Crustacea of Essex have not yet received much 

 attention. Of one among the marine Isopoda however I can speak from 

 personal opportunity. In September, 1895, the British Association met 

 at Ipswich, and at the close of the meeting an excursion was made to the 

 oyster-beds of the Colne. On this occasion not only were thousands of 

 costly and delicious oysters sacrificed to science, but later in the day great 

 quantities of freshly caught Pandalus montagui were consumed in the 



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