A HISTORY OF STAFFORDSHIRE 



Family Cyclopidac. Cyclops quadricornis (Mtlll.). The Four-horned Cyclops or Lesser 

 Water Flea. This species swarms in water that is at all stagnant. I have known it to make its 

 appearance in an elevated roof water-cistern a very few months after the cistern had been made. 

 The eggs must, apparently, have been conveyed to the roof either by rain or wind. 

 Order Rotifera. 



This order, which consists of interesting microscopic forms of life, has generally been 

 classed with the Infusoria : but the organization of the Rotifera shows clearly they naturally be- 

 long to the Crustacea, and that they follow the Entomostraca in a lineal series. The species of 

 this order are not numerous in the district, but Rotifer vulgaris (Ehr.), the Common Wheel 

 Animalcule, is very abundant in the dirt that accumulates in spouts and in roof-gutters, and it 

 is a most pleasing object for the microscope." 



So full and intelligent an account of the Crustacea is quite exceptional in the faunistic 

 catalogues of inland districts at the date when the above report by Mr. Edward Brown was 

 published. That it should now in some points be open to criticism is in no way a reproach, 

 but the natural consequence of such progress as science has happily been making in the 

 interval. Thus, to begin with, the systematic position of the rotifers, as at present accepted, 

 while ranking them far above infusorians, by no means gives them admission into the class 

 with which we are here dealing. There is a vast group or phylum of animals to which 

 Sir E. Ray Lankester has applied the term Appendiculata, because their more or less 

 segmented bodies are capable of bearing on each body-segment a pair of hollow lateral append- 

 ages or parapodia moved by intrinsic muscles and penetrated by blood-spaces. The phylum is 

 divided into three sub-phyla, respectively called Rotifera, Chaetopoda, Arthropoda. See- 

 ing that the Chaetopods or true worms are interposed between the first of these groups and the 

 Arthropoda, with jointed legs, to which the crustaceans and other important classes belong, 

 the relationship between a rotifer and a shrimp is evidently very remote. In the general 

 history of animals this relationship is not to be disregarded, but it will not justify the inclusion 

 of creatures so very distinct in one and the same class. 



The genera and species mentioned by Mr. Garner and Mr. Brown are not very 

 numerous, compared with the whole number which will beyond doubt be eventually found 

 within the waters of Staffordshire. But few as they are, they fortunately spread themselves 

 over most of the chief sections of the class likely to be represented in the district. Any one, 

 therefore, who made himself acquainted with these examples alone would lay the foundation 

 for a very complete mastery of the whole subject. He would have to do, however, only with 

 two of the sub-classes, the Malacostraca and Entomostraca, and in the former he would make 

 no intimacy with the stalk-eyed, ten-footed, short-tailed, true crabs, the Brachyura. This 

 highly organized group might be inclined, after Dr. Plot's example, to lump together almost 

 all other crustaceans as being in comparison with their own intelligent selves mere brutes. In 

 the tropics they have indeed some worthy competitors among the Macrura anomala. But 

 none of the specially gifted land crustaceans have been attracted to our uncertain climate. In 

 the central parts of England the highest representative of the class is the podophthalmous, 

 macruran decapod, already often mentioned, Potamobitu pallipes. This is included with the 

 lobster in the tribe Astacidea, but belongs to a separate family, the Potamobiidae. As being 

 podophthalmous the river crayfish shares with an endless variety of crabs, lobsters, prawns, and 

 shrimps, the peculiarity of having its eyes on movable stalks or peduncles. The theory is that 

 the organs of vision have been developed on the pair of appendages pertaining to the first body- 

 segment, although in almost all cases the segment itself has become immovably fused with the 

 segment behind it. Also in common with the animals classified in popular speech under the 

 four names above given, the crayfish is a decapod. Its ten feet are distributed in pairs to the 

 body-segments numbered from the tenth to the fourteenth. The Malacostracan body is 

 composed of twenty-one segments, each of them, with doubtful exception of the last, being 

 endowed actually or potentially with a pair of appendages. More or fewer of these are called 

 feet, according as they show more or less plainly an analogy with the legs and arms of verte- 

 brate animals. From crabs the crayfish is separated by being macrurous or long-tailed. Yet 

 in both the tail or pleon consists of the last seven body-segments, from the fifteenth to the 

 twenty-first. But somehow, apart from the question of length or shortness, an additional 

 distinction has arisen, that, while in the genuine Macrura the last segment but one always 

 carries a pair of appendages, this pair is always wanting in the genuine Brachyura. 



The drop in dignity is rather abrupt from the only stalk-eyed decapod which our inland 

 counties possess to the Edriophthalma tetradecapoda, or sessile-eyed, fourteen-footed Malacos- 



11 Op. cit. (1863), p. 132. 

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