A HISTORY OF SUFFOLK 



borrowed plumes and scraps of clothing they seek to efface themselves. Not only do they 

 allow weeds and sponges and other zoophytes to grow upon their carapaces, but of their own 

 accord carefully aiBx them. What thus they don, they can also at their pleasure doff. To this 

 tribe, in the family Inachidae, belongs the species Macropodia rostrata (Linn.), which Mr. Claude 

 Morley in 1893 observed in the Ipswich Museum, the place of capture being recorded as South- 

 wold. Mr. Morley laments that at a later date the record of locality had been removed from most 

 of the crustacean specimens in this museum. The nearly related species M. tenuirostris (Leach) is 

 reported by Metzger^ as taken by the Pommerania in 23 fathoms depth, south-east of Yarmouth. 

 In the same tribe Hyas araneus (Linn.), of the family Hyadidae, is recorded by Mr. Morley as 

 brought in by Southwold fishing-boats, and it may be added that in May 1907 a dead specimen 

 was picked up on the north beach at Lowestoft. Among the characters which serve to distin- 

 guish these species one from another, it may be noted that in the genus Hyas the tail-part or pleon 

 is divided into seven segments, a number never exceeded in any malacostracan pleon, though it is 

 often enough apparently not attained. In Macropodia the number is only six, owing not to any 

 real loss of a segment, but to a coalescence which has taken place between the sixth and the seventh. 

 In this genus also the eyes have no proper orbits, but are salient and non-retractile, whereas in Hyai 

 there is a cup-like hinder portion of the orbit into which the eye can be deflexed. Between 

 M. rostrata and M. tenuirostris one mark of difference is that the two closely adjacent arms of the 

 rostrum in the former are shorter, and in the latter species longer, than the peduncles of the second 

 antennae. In both the rostrum is more slender than in Hyas. For both the generic name 

 Stenarynchus, Lamarck, 1818, was long accepted, but Macropodia was instituted by Leach for the 

 same species three years earlier. M. tenuirostris of Leach was for some time supposed to be a 

 synonym of Inachus longirostris (Fabricius). The latter form, however, has now been shown by 

 Miss Rathbun to be a synonym of M. rostrata, so that M. tenuirostris takes rank as an independent 

 species. 



Less interesting to the intellect but more welcome to the palate is Cancer pagurus, Linn., the 

 well-known representative of the Cyclometopa, or arch-fronted crabs. It belongs to the family 

 Cancridae, and for mere purposes of recognition would not need to be described. It may, however, 

 be noticed that technically the front of a crab is the part of the carapace between the orbits, but 

 when we speak of cyclometopous or circular-fronted crabs, we refer to the segment of a circle 

 including with the true front and the orbits also the two marginal spaces, which are commonly 

 divided each into five teeth. These spaces in the great eatable crab form, in place of five dents, 

 nine bluntish lobes. The supply of this species at Lowestoft in the spring of 1907 did not appear 

 to be especially plentiful. Mr. Claude Morley notes that the Ipswich Museum possesses an abnormal 

 claw of a specimen from Aldeburgh. In the same institution he observed Portunus marmoreus. Leach, 

 brought in by Southwold fishing-boats, and Carcinus maenas (Linn.), which he speaks of as doubtless 

 abundant. A dead specimen was noticed in 1907 at Lake Lothing, and incidentally the species is 

 mentioned as occurring in the river at Yarmouth in 1869. While waiting for the tide to turn, 

 ' Robertson and Brady sat down by the side of a little stream, where a great many shrimps were 

 playing or hunting for prey under a little cascade. There was a little shore-crab, Carcinus maenas, 

 stationed at the corner, making many a grab at the shrimps, but they eluded each and every attempt 

 he made by bounding backwards with wonderful dexterity.' ' The genera Carcinus and Portunus both 

 belong to the family Portunidae or swimming crabs, and agree in regard to the pleon, which in the 

 female is fully segmented, but in the male has only five segments, the middle three in that sex 

 being coalesced into a single piece. In Portunus the last joint of the last legs (fifth pair of perae- 

 opods) is far more expanded than in Carcinus. Really the audacious C. maenas is so much given 

 to walking about in the open air that a specially paddle-shaped toe for natatory purposes would be 

 an inconvenient piece of equipment. 



The Oxystomata, or sharp-mouthed crabs, owe their name not to any rostral prolongation, but 

 to the narrowing forwards of the buccal or mouth area. From this tribe Metzger reports Ebalia 

 cranchii. Leach, as taken in 23 fathoms, south-east of Yarmouth, and E. tumefacta (Montagu) in 

 23 fethoms, east-south-east of the same town.' They belong to the family Leucosiidae, in which 

 the afferent channels to the branchiae open at the antero-lateral angles of the endostome or 

 buccal cavity, and the efferent channels traverse it in the middle line. The branchiae are fewer 

 than nine in number on each side. According to Leach, Montagu's species has only three 

 tubercles on the carapace, while his own has five. He further specifies that in Montagu's species 

 the pleon of the male has not only the third to the fifth segments coalesced, but also the sixth and 

 seventh, the latter two apparently being separate in C. cranchii. To an eye unsophisticated by 



' Nordseefahrt der Pommerania (Jahresbericht coram, zur wissenschaftlichen Untersuchung der deutschen 

 Meeres in Kiel, 1875), 294. 



' The Naturaftst of Cumbrae (1891), 256. • NordseefoArt der Pommerania, 293. 



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