Febbuary 1, 1899.] 



KNOWLEDGE. 



29 



It cannot be said that any of these birds is restricted to 

 one set of tones both for anger and for song (as occurs to 

 some extent in the common duck), for all of them have 

 special cries of alarm and anger, which they utter when 

 frightened by a predaceous beast. The robin employs his 

 rattling note of alarm ; the thrush, when its nest is 

 threatened by the jackdaw, makes a great outcry like that 

 of the mistle thrush ; the tree pipit has an alarm which 

 is given when the nest is threatened ; the brown wren 

 repeats a common note when frightened : and the others 

 have a similar variety of cries. 



These remarks are intended to prove the importance of 

 carefully analysing a bird's notes before attempting to 

 define their meaning. The subject is so new that anyone 

 who will carefully notice may do good work, and at no 

 cost of bird-life. Nor can it reasonably be urged that this 

 analysis would rob the poet of some common symbols. 

 No one would unnecessarOy deprive him of any, but he 

 should know that while the blackbird, starling, chaffinch, 

 and others may be pouring out the truest love-notes, the 

 robin, thrush, hedge-sparrrow, and others, though also 

 singing, may be using the very "Billingsgate" of birds. 



THE KARKINOKOSM, OR WORLD OF 

 CRUSTACEA.-VII. 



By the Rev. Thomas R. R. Stebbing, m.a., f.r.s., f.l.s., 

 F.Z.S., Author of " A History of Crustacea," " Tlie 

 Xaturalist of Cumbrae," " Report on the Amphipoda 

 collected by H.M.S. ' Challenyer,' " etc. 



THE BOX CRUSTACEA. 



IN an essay on Boxes, a writer might find a cue for 

 discussing the merits of thrift and the weakness of 

 the miser, the proper and the improper discipline of 

 children, the implements of a laundry, the arrange- 

 ment of a theatre, the situation of a country seat, 

 the structure of a cart-wheel, a pump, or a drain. He 

 might speak of trees and their uses, of coaches, of coats, 

 and of Christmas presents. He would, naturally, consider 

 the receptacles which have been contrived for keeping the 

 garments of the living and the remains of the departed. 

 To add to this miscellaneous assortment a mention of the 

 Box-crabs would be an unfruitful eccentricity, because the 

 species of Calappa which have been so designated, though 

 highly curious in themselves, are no more boxes than crabs 

 in general. But, for all that, there is a veritable group 

 of Box Crustacea. Here the boxes are alive, and, besides 

 being just large enough for what the owner wants to keep 

 in them, they have the magic faculty of increasing in size 

 exactly to match the increase of the contents. The animals 

 of this group are known to science as the Ostracc'ida, the 

 shelly group, so-called because they bear an external 

 resemblance to " shell-fish, " to bivalved moUusca, such as 

 mussels and cockles. They have, therefore, no sort of like- 

 ness, outwardly, to tbat popular ideal of a crustacean, 

 which hovers between a crab and a shrimp, but must be 

 compared with other entomostracans, such as the Estheria 

 figured in our first chapter, or the Daphnia in our fourth. 



The collector of crabs and lobsters is apt to scare the 

 members of his household by the odour of the specimens, 

 if he keeps them dry, or by the continued demand for 

 bottles and corks of all sorts of unprocurable sizes, if the 

 specimens are to be preserved in spirits or formalin. 

 House-room also soon becomes a consideration. But with 

 the Ostracoda it is different. Many of them are less than 

 one millimetre in length, and they are seldom broader than 

 long. Now, a millimetre is just a twenty-fifth part of an 

 inch ; see, then, how convenient it is for a naturalist, whose 



Poll/cope orbictilarh Sars, lateral and dorsil 

 views. From G. S. Bradv. 



space accommodation is limited, to be able to place six 

 hundred and twenty-five specimens on a plot of ground, or 

 a piece of black card, an inch square. 



To the unscientific Briton it may appear pedantic, 



unpatriotic, 

 and needlessly 

 obscure to give 

 scientific mea- 

 surements in 

 French milli- 

 metres. But 

 there is this 

 important con- 

 venience in it, 

 that a milli- 

 metre means 

 the same mea- 

 surement all 

 the world over, whereas the English word " inch " trans- 

 lated into the French "pouce,' or the German " Zoll," 

 changes its meaning at each step, the German inch being 

 equivalent to twenty-six millimetres, while ours answers 

 to twenty-five and the French to twenty-seven. Now that 

 science has become more than ever cosmopolitan, it is a 

 serious evil to use words such as inch and foot and fathom, 

 which are untranslatable, except by the help of a sum in 

 fractions. 



With the Ostracoda, at all events, the millimetre will 

 be found to be a specially suitable unit of measurement. 

 Their personal proportions never require to be reckoned 

 in feet or in inches. Nevertheless, as in all other groups 

 of animals, there are among them disparities of size, from 

 the dwarfish to the elephantine, but still all within a 

 modest, unalarming compass. Their delicate little corpses 

 dry up within their own organic sarcophagus, and need no 

 embalming to make them inoffensive. They remind one 

 of that romantic country in which the old men never died 

 but only shrivelled, and could, by process of steeping in 

 hot water, be occasionally revivified to answer the enquiries 

 of a younger generation. In regard to some of the speci- 

 mens described in the " Monograph of the Marine and 

 Fresh-water Ostracoda of the North Atlantic and of North- 

 western Europe " (1896), the authors. Dr. G. S. Brady 

 and Canon Norman, say, " it struck us that, notwith- 

 standing their dried condition, it might yet be possible by 

 maceration to get some idea of the withered inmates of the 

 shells. We therefore made experiments, and succeeded 

 in restoring the animals beyond our most ardent expecta- 

 tions.' ' The authors are evidently innocent of any suspicion 

 that the process had ever been applied with equal success 

 to human beings. 



Besides being easy to keep and hard to decay, the Ostra- 

 coda have another advantage in the universality of their 

 aquatic distribution, so that some of the species are ex- 

 tremely easy to obtain. Not only are these organisms 

 distributed over all the water-covered floor of the existing 

 world, but their range extends through the fossiliferous 

 strata from the Cambrian to those which are now being 

 formed. It must, however, be admitted, and should be 

 borne in mind that we cannot macerate carboniferous or 

 cretaceous forefathers of the Ostracoda. They no longer 

 yield to any witchery of rejuvenescence to answer our 

 questionings. Only the boxes, the external valves, remain, 

 preciously imperishable, saved, as the moralist may be 

 pleased to observe, not by any heroic grandeur but by their 

 insignificant smallness, and a mean dwelling in the slum- 

 berous ooze. The strong likeness between the valves of 

 some species still hving and the fossil valves belonging to 

 I various geoloeical periods makes it probable that in the 



