r.UANCHlOPODA. 



BRAXCHIOPODA. 



in the Hastings Sand*. Desmarest notes the ipeci< u found in (rreat 

 abundance new th* mountain of Oerguvic, in the department of the 

 Puy-de-Dome, and at the Balroe-d'AUier, between Vichy-les-Bains and 

 Their great fruitfulneu and the frequent moulU noticed 



Cyprit ornata (magnified). 



Shell yclloniiih-frccn, banded with green. A, side view ; B, view looking 

 upon the hinge. The hanJs commence behind the eye. 



Cypriifutca (magnified), Straus. 



Valves brown, kidney-shaped, covered with fine scattered hairs. Antenna' 

 with fifteen fine bristles. In the view the valves are supposed to be removed, 

 the outline a a showing their shape and their relative situation ; 6, origin of 

 the hinge membrane ; c t eye ; d d, antenna} deprived of their bristles ; e, feet 

 of the first pair ; /, of the second pair ; g, of the third pair ; h, tail ; i, labrum ; 

 k, mandible ; (, feeler ; m, jaw of the first pair ; , of the second pair ; 

 o, branchla or gill ; p q, posterior portion of the left ovary ; r, the male organ 

 according to Straus. 



above may account in some measure for the quantities of their 

 petrified exuviae. Cyprit has also been found in the Fresh-Water 

 Limestone, beneath the Mid-Lothian Coal-Field, at Burdiehouse, near 

 Edinburgh, and in other districts. 



Cladoctra, Latreille ; Daphnidti, Straus. These minute creatures 

 have a single eve only, and are protected by a shell doubled as it were, 

 but without any hinge, according to J urine, and terminated posteriorly 

 in a point The head, which is covered with a kind of beak-like 

 armour, projects beyond the shell. There are two antennae, generally 

 large, in the form of arms, divided into two or three branches placed 

 on a peduncle fringed with filaments always projecting, and serving 

 the purpose of oars. The feet, four to six pairs, terminated by a 

 digitated or pectinated swimming organ, and furnished, with the 

 exception of the two first, with a branchial lamina. Their eggs are 

 situated on the back, and their body terminates with a sort of tail 

 with two delicate hairs or filaments at the end. The anterior part of 

 the body is aomtimes prolonged into the form of a beak, sometimes 

 into a shape approaching that of a head occupied almost entirely by 

 one large eye. 



Latreille gives the following sub-genera : Polyphemut, Miiller ; 

 Daphnia, Muller ; Lynceut, Mull.* (Chilodorut, Leach). This division 

 in Baird's ' Entomostraca ' includes the following families and genera. 



Daphnia. 

 Botmina. 

 Sida. 



Polyphemut. 



Swryeercut. 

 Camptocercut. 

 Alma. 

 Peracantha. 



Muina. 



2. Polyphemida. 

 8. Lynct'tdir. 



Daphnella. 

 Eradne, 



Chydorut. 

 Acropemt. 

 I'leuroxut. 



Of these Daphnia is the most numerous genus ; and though the 

 species are so extremely small, the observations of naturalists, and 

 BMM especially of SchoeSer, Bamdohr, Straus, and the elder J urine, 



have rendered its organisation and habits extremely well known. In 

 the species of Dapknia one junction of the aexes fecundates the ova 

 for many successive generations, six at least; their moults are 

 very frequent ; they lay at first but one egg, then two or threo, and so 

 on progressively as they advance in life till their number amounts to 

 68 in one species (Uapknia tiiayna) ; and the young of the same 

 deposit are generally of one sex, it being rare to find two or three 

 males in a female batch, and vice versa. As the winter approaches 

 their moults and oviposits cease, and the frost is supposed to destroy 

 them, leaving however the eggs unharmed, which the genial spring 

 season hatches to fill the pools with myriads of Daphnia. Then 

 those who have microscopes will find ample employment for them. 

 Every ditch, every pool, every garden reservoir, will furnish the 

 observer with Branch iopoils. 



The species are numerous. The most common is the Water-Flea, 

 Daphnia puUx of Latreille, Munoculiu puirjc of Linnaeus, Pules 

 aquatiou arboraccnt of Swaminerdam, Le Perroquet d'Eau of 

 Geoffrey. Despised as this minute creature may be by those who, 

 like the orientalists, consider size as absolutely necessary to produce 

 grand ideas, it has fixed the especial attention of Swammerdam, 

 Needham, Leuwenhoek, Schooffer, De Oeer, Straus, and above all, of 

 .1 iii-iii.', who, in common with other philosophers of great name, have 

 found as much interesting information regarding the development 

 of animal life in the admirable organisation of these animated specks 

 as is afforded by the largest vertebrated animal [DAPHNIA.] 



Section II. 

 PhyUopa. 



Distinguished by the number of feet, and by the lamella or folia- 

 ceous form of the joints, representing, according to Latreille, the 

 Myriapodi in the class Intecta. The eyes are always two in number, 

 formed of a sort of network, and sometimes placed on pedicles ; many 

 have besides a single smooth eye. 



Cerat^phthalma, Latreille, have ten pairs of feet at the least, and 

 the maximum of those organs in this group is said to be 22. There 

 is no vesicular body at their base, and the anterior feet are never so 

 long as the others, nor are they ramified. The body is either inclosed 

 in a shell-case, like a bivalve shell, or naked, the thoracic divisions 

 being each furnished with a pair of feet. The eyes are sometimes 

 sessile, small, and placed very nearly together ; sometimes, and indeed 

 most frequently, they are mounted on the extremity of two moveable 

 pedicles. The eggs are either internal or external, and inclosed in a 

 capsule. 



a. 



Eyes sessile, iinmoveable ; body inclosed in an oval case like a 

 bivalve shell ; ovaries always internal 



The sub-genus Limnadui of Adolphe Brongniart is an example of 

 this structure. Limnadia ffennanni (Adol. Brongn.), Daphnia gigat of 

 Hermann, occurs in great numbers in the little pools of the forest of 

 Fontainebleau, and we must refer the reader to Bronguiart's Memoir in 

 the 6th vol. of the 'Me'moircs du Museum d'Histoire Naturelle ' for 

 its description. 



0. 



Each eye situated at the extremity of a pedicle on both sides of the 

 head; body naked and anmilute<l throughout its length; no 

 enveloping case or shell ; eggs contained in an elongated capsule 

 situated towards the base of the tail, or at the posterior extremity of 

 the body and thorax in those which have no tail. 



1. With a Tail. 



To this subdivision belongs the Brine-Shrimp or Brine-Worm, 

 Artcmia or Artemis of Leach, Branchiput of Latreille, and Cltirocejiha/ta 

 of Benedict Prevost and Jurine. We are now arrived at that develop- 

 ment of form in the Branchiopods where the numerous legs or feet 

 become paddles adapted simultaneously to the purposes of locomotion 

 and respiration. 



The Brine- Worm or Brine-Shrimp, Artemia talina of Leach, Cancer 

 talinat of Linnaeus, Gammaru* laliniu of Fabricius, Artemit talinut of 

 Leach, A rtomitut talinut of Lamarck, when full-grown, is about half 

 an inch in length and very transparent : it is said to have been first 

 discovered in the salt-pans at Lymington by Dr. Maty. There these 

 animals are found in myriads, in rapid and continual motion in the 

 salterns, which are the open tanks or reservoirs where the brine is 

 deposited previous to boiling. The brine attains the desired strength 

 by evaporation from exposure to the sun and air in about a fortnight. 

 A pint contains about a quarter of a pound of salt, and in this 

 concentrated solution, which, as Mr. Rackett observes, instantly 

 destroys most other marine animals, the Brine-Shrimp revels. It U 

 further said that these Brine-Worms are never found in the sun-pans 

 where the brine is made by the admission of sea-water during the 

 summer, and which are emptied every fortnight, but only in the pits 

 or reservoirs (clearer*) where it is deposited after it is taken out of 

 the pans, and where some of the liquor constantly remains. So 

 persuaded are the workmen of their utility in clearing the liquor, that 

 they are accustomed to transport a few of the worms from another 

 saltern if they do not appear at their own, and they increase greatly 

 in a few days. Little however was known of the natural history of 

 this animal till Mr. Thompson published his interesting observations 

 in the 6th number of his 'Zoological Researches' (1834). He has 



