THE BOEING AMPHIPOD. 825 



water mark. The males are much larger than the females, and sometimes become nearly an inch 

 and a half long. They cannot leap like their cousidfr that live at high-water mark, but skip 

 actively about on their sides among the stones and gravel until they reach some shelter or 

 enter the water, when they swim rapidly in a gyrating manner back downward or sideways. 

 But although they can s\^im they are seldom met with away from the shore or much below low- 

 water mark. The zone of Fucus is their true home. This species is abundant on all our shores, 

 wherever rocks and Fucus occur, from Great Egg Harbor, New Jersey, to Labrador. Its color 

 is generally olive-brown or reddish-brown, much like that of the Fucus among which it lives. 

 The only good English name that I have ever heard for these creatures is that of < Scuds,' given 

 by a small boy, in reference to their rapid and peculiar motions. . . . Two other related 

 species, of larger size and paler colors, but having the same habit of leaping as the Orchestia, 

 though not in such a high degree, occur among the weeds, or burrowing in the sand, or beneath 

 drift-wood, etc., a little below high-water mark. In fact, the sand is sometimes completely filled 

 with their holes, of various sizes. Both these species are sto'ut in form, and become about an 

 inch long when mature. One of them, Talorchestia longicornis, can be easily distinguished by 

 its very long antennae; the other, T. megalophthalma, by its shorter antennse and very large eyes. 

 Both these species are pale grayish, and imitate the color of the sand very perfectly. When 

 driven from their burrows by unusually high tides or storms they are capable of swimming 

 actively in the water. They make dainty morsels for fishes and many shore birds, as well as for 

 certain Crabs, especially Ocypoda arenaria."^ 



The B0RIN& AMPHIPOD — Oheltjra terebrans, Phillipi. 



This very destructive little crustacean, which is of common occurrence on the European 

 coast, from Southern Norway to the Adriatic Sea, has so far been noticed on the Atlantic coast 

 of the United States at only two places. Wood's Holl and Provincetown, Massachusetts. At 

 both of these localities it was found associated with the "Gribble" (Limnoria lignorum), in the 

 submerged piles of old wharves. It is more than possible, however, that it is a common inhabitant 

 of our coast, doing a certain amount of the damage hitherto ascribed to other boring animals. 

 Without a careful examination, it is quite easy for an unskilled eye to confound Ghelura with 

 Limnoria, although they belong to very distinct divisions of the Crustacea. 



The main characteristics of this animal by which it may be distinguished from all the other 

 Amphipods, as well as crustaceans, are the three pairs of caudal stylets, the last pair being 

 nearly as long as the body p'roper of the males, although much shorter in the females and young. 

 As to color, the body is semitranslucent and thickly spotted and mottled above with pink. 



Professor Allman, of England, who has studied living specimens, describes the habits of 

 this species as follows:^ 



'■^Ohelura terebrans is an active little animal, swimming on its back and employing its 

 thoracic legs to adhere to the timber which it has selected for its ravages. ... Its habits 

 are truly xylophagous, and it excavates the timber not merely for the purpose of concealment, 

 but with the object of employing it as food, which is apparent from the fact that the alimentary 

 canal may be found on dissection filled with minutely comminuted ligneous matter. . . . 

 Timber which has been subject to the ravages of Ghelura presents a somewhat different 

 appearance from that which has been attacked by Limnoria lignorum. In the latter we find 

 narrow cylindrical burrows running deep into the interior, while the excavations of Ghelura are 



' Vekeill : Vineyard Sound Eeport, pp. 313, 314, 1871-'72. 

 ^Ann. and Mag. Nat. Hist., xix, p. 361, 1847. 



