673 



THIRD DIVISION, CLASSES— CRUSTACEA, ARACHNIDA, 



AND INSECTA. 



CRUSTACEA. (P. 407—448.) 



The British Malacostracous Crustacea form the subjects of two valuable works ; one, by Dr. Leach, in quarto, 

 with beautiful coloured plates, representing each species of the natural size ; and the other now in course of pub- 

 lication by Professor Thomas Bell, forming part of Mr. Van Voorst's beautiful series of works upon British 

 Natural History. 



An invaluable series of illustrations of the whole of the class Crustacea, has been published by Milne Edwards, 

 in the Crochard edition of the Regne Animal. 



The Crustacea of D'Orbigny's Voyage have also been more recently described and beautifully figured by MUne 

 Edwards, and those of the voyage of the Samarang, by Mr. A. White (now in course of pubUcation). Other nev/ 

 species have also been described by Mr. White in detached papers in the Annals of Natural History. 



The periodical casting of the shell by these animals after their arrival at their adult form, led to the long-received 

 opinion that they had not previously undergone any decided metamorphosis. The recent investigations of several 

 authors have, however, clearly proved that the young fry in many species are quite unhke their parents, and that in 

 fact they are the animals which had been previously considered as distinct Entomostracans, under the name of 

 Zoea. It is singular, however, that the fry of the common Cray-fish (as observed by Rathke), and of the land Crabs, 

 do not materially differ from the adult state. 



A new and remarkable genus, named Calocaris by Professor Bell, belongs to the Decapod Macroura and subsection 

 Astacini (p. 420), but with elongated limbs, a very thin crust to the body, destitute of all colouring pigment, and of 

 cornea; in the eyes. C. Macandreae, a species found in Loch Fyne and the Mull of Galloway, inhabits a depth 

 of no less than 180 fathoms, where of course distinct vision would be useless and unavailing, which accounts for the 

 rudimental character of the eyes, which are entirely white. 



Dr. Erichson has recently published a memoir on the genus Astacus (p. 420), describing a number of additional 

 species of Cray-fish from various parts of the world. 



Several other new and interesting British genera allied to Mysis (p. 422), have been described by II. Goodsir in 

 the New Edinburgh Philosophical Journal. 



Zeuxo, Templeton in Trans. Ent. Soc. (Z. Westwoodiaiia) ; and Crossurus and Liriope of Rathke (Nova Acta, Vol, 

 XX.) are small but remarkable genera closely allied to Rhsa, p. 428. 



Many additional species as well as several new genera of Amphipoda (p. 429), have also still more recently been 

 described by Rathke, in Nova Acta, Vol. XX., and in Kroyer's Tidsskrift ; and in a very interesting genus named 

 Chclura terebrans, which burrows into submerged wooden structures in the same manner as Limnoria, has also 

 been described by PhiUppi in the fourth Volimie of Wiegmann's Archives. 



H. Goodsir has also added some new and very distinct British species of Amphipods in the Edinburgh New Philo- 

 sophical Journal, Vol. XXXIII. 



H. Goodsir has described a third species of Bopyrus (p. 431) in the Annals of Nat. Hist., Vol. XV., found beneath 

 the carapace of Hippolyte ensiferus ; and Rathke has described and figured, with all its details, a new alUed genus 

 named Phryxus, also found beneath the shells of different Macrourous Crustacea (Nova Acta, Vol. XX.) of which I 

 possess a British specimen. 



A very elaborate paper upon the destructive Limnoria terebrans (p. 432), has been published by Dr. Coldstream 

 in the seventeenth volume of the Edinburgh New PhUos. Journal. 



Two additional British species of Arcturus (p. 433), have also been described by H. Goodsir. 



The development of the eggs and young of Asellus aquaticus (p. 433), has formed the subject of a very elabo- 

 rate memoir by Rathke, published in the second volume of the second series of the Annates des Sciences Natu- 

 relles. 



H. Goodsir has described several new British species of the singular genus Cuma (p. 437), as well as two new 

 and allied genera, named Bodotria and Alauna, in the thirty-fourth volume of the Edinburgh New Philos. 

 Journal. 



Dr. Baird's Papers on different portions of the Entomostraca, published in the Annals of Natural History, must 

 be consulted, and also a paper by the same gentleman, in the first volume of the Zoologist, upon other species 

 which are luminous, and inhabit the ocean ; including the genera Oithona and Cyclopsina. Amongst the minute 

 luminous oceanic species, and probably, in the present order of Branehiopoda, must also be ranged the genus 

 Sapphirina of Edwards, as well as several other minute species and genera recently described by Goodsir, pecu- 

 liar for possessing a double eye in a single dark spot, with the body depressed as in the Isopoda, and the posterior 

 thoracic legs double. They are very active in their habits, and swim about in company with other allied forms. 

 They constitute the genera Zaus, Steropc, and Carillm. The Oniscus fulgens of TUesius seems to belong to the 



