108 THE YOUNG 



to everybody as the little sandhoppers, 

 which are so common among decaying sea- 

 ware about high water mark. The second 

 family, the Gammaridce proper, contains a 

 large number of genera. Not to weary you 

 with a list of hard names, I will only men- 

 tion Gammavus pulex, the little fresh-water 

 Crustacean already mentioned, which is 

 found in all our brooks, and its very near 

 relative, G. locusta, which is equally common 

 in tidal pools ; A tylus Swammerdamii, which 

 is very abundant in deepish water below 

 Point of Ayr ; Calliope leviuscula, common in 

 the same pools as G. locusta; and Aora 

 gracilis, which I took in considerable quan- 

 tities on the common sponge Halichondria 

 panicea, off Rhyl last autumn. The male 

 and female of this species differ so much 

 that the latter has been figured and described 

 by Spence, Bate and Westwood as a distinct 

 Species, viz. Microdentopus anomalus. The 

 third family, Corophiida, forms a separate 

 sub-division of the Gammarina, called the 

 Domicola, from their inhabiting tubes or 

 nests. Of these Podocerus falcatus makes 

 nests in corallines, and is very common ; 

 while Corophium longicovne is probably the 

 most abundant of all our Crustacea, hun- 

 dreds of acres of the muddy banks of the 

 Dee being perforated with their burrows. 

 There is no doubt that they form one of the 

 principal sources of food to the numerous 

 gulls and wading birds that haunt our 

 Estuary. 



The small division of the Hyperina is 

 composed entirely of the small Crustacea, 

 that are fou :d inhabiting the gill-cavities of 

 Medusas. If a freshly stranded Rhizostoma 

 pulmo be examined, the chances are that 

 one or more individuals of this family will 

 be found inside the " umbrella." 



The group of Aberrantia of the above 

 named authors, now generally formed into 

 a separate tribe, placed after the Isopoda, 

 and called Lamodipoda, is represented on 

 our shores by the common skeleton shrimp 



NATUEALIST. 



(Capvella linearis), whose curious antics as 

 as it holds on to a branch of sea-weed by 

 its hind legs must have often amused those 

 of my microscopical friends who have had 

 the smaller sea-weeds, zoophytes, &c, from 

 the lowest tide marks under inspection. 

 The whale lice (Cyamus), are also included 

 in this group. 



The second order of Edriophthalmia con- 

 tains a large number of little known genera 

 and species, many of them parasitic on 

 larger Crustacea. Without entering into 

 their various divisions, I may mention as 

 likely to be met with, Eurydice pulchra, a 

 very actively swimming and prettily marked 

 little creature which is so abundant in the 

 Dee that it is scarcely possible to fish up a 

 bucketfull of water off Bagillt or Mostyn 

 without catching several. It is a voracious 

 little animal, and does not hesitate to attack 

 bathers from a boat, biting very sharply. 

 Janira maculosa is very common on sponges 

 in salt water, and Asellus aquaticus, the only 

 fresh water species, in ponds, &c, Limnoria 

 lignorum (the Gribble), is a serious pest ow- 

 ing to its habit of boring into piles under 

 water. According to Bate and Westwood it 

 is abundant in the Dee, and has done great 

 damage to the "piles supporting the rock 

 lighthouses at New Brighton." I have, 

 however, never seen it myself or any of its 

 ravages in the Dee, though I know two 

 wharves at Bagillt built with wooden piles. 

 Idotea linearis and I. triumpidata are common 

 among sea-weeds, and Spharoma serratum 

 among stones in gravelly places. Ligia 

 oceanica, like a large wood-louse, is said to 

 be found at Llanddulas and as it is com- 

 mon on most shores under stones, I have 

 no doubt that it is. It introduces us to the 

 terrestrial Isopods, or wood-lice, as they may 

 be broadly called. Of these there are six 

 genera and sixteen species described in 

 Bate and Westwood's work, and there is 

 little doubt that if more attention were paid 

 to this neglected group new species would 



