16 



SCIENCE- G OSSIP. 



■other hand, a somewhat well-defined group, the 

 members of which construct abodes in which they 

 take shelter and nourish their young. Such abodes 

 are of various forms ; often tubular, but sometimes 

 bird's-nest like ; others are built with weed and 

 various objects cemented or fastened together, or 

 they may be of mud, while in some cases the 

 ■creatures dig passages in clay, or burrow into 

 timber or even harder substances. It is in the 

 construction of certain of these abodes that the 

 spinning powers of Arnphipods are chiefly employed ; 

 and indeed I do not know that their threads have 

 any other use. The kinds with which we are con- 

 cerned belong chiefly to the family Corophiidae, 

 .at least in the wide sense in which that title was 

 formerly employed ; but to conform to the views 

 of recent authorities it is necessary to say that 

 they belong also to Podoceridae, Photidae, and 

 •other families. 



Among the few of these Amphipod-homes to 

 which naturalists have given attention are the 

 fixed more or less tube-like abodes of AmpJiitTwe 

 rubricata. This animal is about half an inch long, 

 and sometimes of a bright crimson colour ; and, 

 according to Bate and Westwood, it generally lives 

 in a nest of its own construction, at the roots 

 of Laminariae and other plants, or on the under- 

 sides of stones, at a few fathoms' depth of water. 

 In making the nest the animal scratches together 

 various available materials ; but the point of 

 interest for us is that a minute examination of the 

 collected matter shows it to be united by a 

 quantity of fine threads, which, crossing each 

 other in a confused manner, are closely woven 

 .and knitted together. Some individuals in 

 captivity were observed to build nests against the 

 glass of the vessel in which they were kept ; and 

 under the microscope these nests were found by 

 -the authors just named to be composed of many 

 bits of weed," matted together by means of ex- 

 quisitely delicate threads, which had the appearance 

 of having been spun or twisted, numerous small 

 loops being formed by threads intertwined. Some 

 nests of the same Amphipod received by these 

 authors from Banff consisted chiefly of this fine 

 thread, with which only a very little foreign 

 material was built in with the structure. Of 

 Amphitltoe littorina, formerly considered distinct, 

 but now merged with AmpMthoe rubricata, the 

 authors describe a nest constructed of bits of 

 weed, sand, etc., bound" together by fine threads; 

 but they believed that the creature frequently 

 Tolled and cemented together the edges of a leaf 

 ■of growing seaweed, forming a tube open at each 

 end ( 2 ). 



More curious are the abodes of Jcmassa capil- 

 lata (Podocerus capillatus), a little Amphipod 

 about a quarter-inch long, and beautifully varie- 



(2) Bate and Westwood, "British Sessile-eyed Crustacea," i. 

 ■(1863), pp. 418-425; Bate, " Nidi neat ion of Crustacea," "Ann. 

 and Mag. of Nat. Hist." (3), i. (1858), pp, 161-169. 



gated in colour. It is shown by Bate and West- 

 wood to build, in diminutive submarine forests, 

 little nests, recalling in an unmistakable manner 

 those of birds. These nests, built and firmly 

 established in the branches of zoophytes and algae, 

 consist chiefly of fine thread-like material, woven 

 and interlaced. Some small extraneous fragments 

 ate often bound into the structure ; but these, it is 

 thought, are more the result of accident than of 

 intention. In form the nest is somewhat oval, the 

 entrance being at the top. It is evidently used as 

 a place of refuge ; but it serves, at the same time, 

 as a true nest, in which. the mother protects her 

 brood of young until they are old enough to be 

 independent of her care. Bate and Westwood 

 figure a group of these structures from the Cornish 

 coast, built in the slender branches of a Plvmit- 

 laria, and certainly appearing surprisingly like 

 diminutive birds'-nests, though the opening at the 

 top is smaller ii* proportion to the rest of the 

 structure than in the ordinary form of bird's-nest. 

 One of the nests from this group, on being opened, 

 was found to be occupied by a mother and a 

 swarm of young, the latter evidently of two .ages, 

 and therefore of two broods. The authors received 

 nests of the same Amphipod from rock-pools near 

 Banff,, built in this case in Corallina officinalis ( 3 ). 

 Further recalling birds'-nests, not in shape, but 

 from the miscellaneous objects of which they are 

 composed, are the tubes of an- Amphipod allied to 

 Ericthonius difformis, in which Mcintosh found, 

 besides mud and cement, " grains of sand, bristles 

 and spines of annelids, hairs of sea-mice, and many 

 fine horny fibres, apparently derived from the byssi 

 of horse-mussels " ( 4 ). 



The small tube-like abodes of the little Mi ero- 

 deutopus gryllotalpa have been studied by S. I. 

 Smith, of New Haven. Those examined were built 

 amongst small branching seaweeds, and were found 

 to be composed, largely, of a network of fine 

 threads of cement ( s ). Smith originally described 

 the animal as 3Iicrodevtopus minax, but subse- 

 quently referred it to J/, grandimamis, which 

 name, according to Boeck and Sars, is«a synonym 

 of M. gryllotalpa ( 6 ). 



In Cerapus the tube, instead of being fixed, is 

 free, and is carried about by the animal, like the 

 case of a caddis-larva ( ; ). Some doubt has been 

 entertained as to the origin of this tube, Say 

 having supposed it to be that of some other 



(3) Bate and Westwood, lorn. cit. pp. 442-444. 



(4) Mcintosh, " Ann. and Mag. of Nat. Hist." (5) xvi. (1885), 

 pp. 484. 



(5) S. I. Smith, "Trans. Connecticut Academy," iv. (1882), 

 pp. 274, 275. 



(6) Stebbing, " ' Challenger ' Beports," xxix. (1888), pp. 435- 

 437 ; Sars, " Crustacea of Norway," i. (1895), pp. 543, 544. ' 



(7) Say, on Cerapus tubularis (New Jersey), "Jourii. Acad. 

 Nat. Sci. Philadelphia," i. (1817), pp. 49-52 ; Templeton, on 

 Cerapus abditus (Mauritius ?), " Trans. Ent. Soc. London," i. 

 (1836), pp. 185-190 ; Sars, on Cerapus crassicornis (Norway), 

 turn. cit. p. 609; Giles, on Cerapus calamicola (Bay of Bengal), 

 " Journ. Asiatic Soc. of Bengal," liv. (1887 ), pt. 2, pp. 54-59. 



