84 



called Ophidium imberbe, Brit. Zool. App. iii., is marked in pencil, 

 apparently by Dr. Solander, as being " Murcena Anguilla.'" This 

 probably explains why the figure is replaced in the edition of 1812 

 by Montague's figure from the Wernerian Transactions, as mentioned 

 by Yarrell, Brit. Fishes, 412 & 414, where these two figures are 

 copied. 



Since this paper was read, there has appeared in the ' Annals of 

 Natural History ' a full description of Mr. Whitehead's specimen, and 

 an accomit of some other specimens found on other parts of the En- 

 glish coast. 



3. Monograph of the Family Limnadiad^e, a family of 

 Entomostracous Crustacea. By W. Baird, M.D., F.L.S. 



ETC. 



(Annulosa, PI. XL) 



Jean Frederic Hermann, in his ' INIemoire Apterologique,' published 

 at Strasbourg in 1 804, described and figured an Entomostracous crus- 

 tacean, which from its resemblance to the genus JDaphnia of Miiller 

 and its large size, he called Daphnia gigas. About thirty years pre- 

 vious to that time, he tells us, his father discovered a number of these 

 interesting Httle animals in a deep ditch near Strasbourg filled with clear 

 rain-water and well-stocked with weeds. Struck with their beauty he 

 collected several dozens of specimens, and placing them in a vessel full 

 of water less pure than that which the ditch contained, took them 

 home. By the time he reached his house however they were all dead 

 but one, and he only succeeded in preserving two specimens in spirits 

 of wine. Linnaeus had long before that described a species of Mono- 

 culus in his ' Fauna Suecica,' under the name of Monoculus lenticu- 

 laris, fomid in Finland. His description is very brief, and Her- 

 mann (pere) considering it probable that his animals might be iden- 

 tical with the species described by Linnseus, preserved the shells or 

 bucklers of the little creatures which had died, and distributed them 

 among his friends and correspondents. He sent some more particu- 

 larly to the celebrated Miiller, at that time engaged in working out 

 the history of the Entomostraca, and entreated him and his other 

 friends to inform him if they considered the specimens he had sent 

 to be identical with the Monoculus le)iticularis of Linnseus. Miiller 

 and his other correspondents all replied that they were not able to 

 inform him, as they did not know Linnseus' s insect — and from that 

 time up to the period at which the younger Hermann's 'Me'moire 

 Apterologique ' was published, neither father nor son had ever again 

 succeeded in finding these animals. Nothing farther seems to have 

 been known of any species belonging to the family till M. Adolphe 

 Brongniart in 1820, in the sixth volume of the * Memoires du Museum 

 d'Histoire Naturelle,' pubHshed a description of an animal found by 

 him in a pool of fresh water at Fontainebleau, which he considered (I 

 think erroneously) as identical with the Bajihnia gigas of Hermann. 

 Of this species he formed his genus Limnadia, and at the same time 

 entered fully into the details of the structure and habits of the ani- 

 mal. In the 'Bulletin de la Societe Impc^riale des Nat. de Moscou ' 



