28 PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXVII. 



Chiridotea saUna (Kr0yer), Chiridotea entomon (Linnaeus), and 

 Gli/ptoiwtus antaHlcus Eights « being found in the Frigid Zone or 

 Arctalian Realm/ 



The Sphffiromidte are nearly all cold-water species, though not reach- 

 ing into the Arctalian Realm. Sphseroma thermophiluiih Richardson, 

 from a warm spring in New Mexico, and S. dugesi Dollfus, also from 

 a warm spring in New Mexico, are exceptions. 



The Idoteida^ are the most decidedly cold-water forms, the Cymothoi- 

 daj and the Corallanid* the least so. 



The following genera extend into the Arctalian Realm: Idotea^ 

 Glyptonotus^ Jmra, Janira^ Munna^ vEga^ Serolis, Gnathia, Arcturus, 

 Timais, Ziriopsis^ Phryxus, Dajus, GMridotea^ Gryptocope, Leptogna- 

 thia, Sphyrapus, Synidotea^Astacilla, Munnopsis^Eurycope, GalatJmra^ 

 and Bojyyroides. 



In the Pararctalian and Notalian realms there is a commingling of 

 forms from the Arctalian, Antarctalian, and Tropicalian realms. 



Some of the terrestrial Isopods are very widely distributed, such 

 well-known species a,8 ArmadilUdrunividgare (IjntreiWe) , Porcelllo Isevis 

 (Latreille), Porcellio scaber (Latreille), Oniscus asellus Latreille, and 

 Metopxmorthu^ pnmiosiis (Brandt) being cosmopolitan and found all 

 over the world. 



Many of the marine forms from the coast of Norway, England, and 

 the Atlantic coast of Europe, and from the Mediterranean are carried 

 b}^ the Gulf Stream along the Atlantic coast of North America and are 

 found on the coast as far south as the West Indies and the Bermudas. 

 Among the number on record from European waters found on the 

 Atlantic coast of North America may be mentioned: Idotea metallica 

 Bosc, Rocinela maculata Schicedte and Meinert, JEga ventrosa M. 

 Sars, ^ga urcth-a Liitken, Sphyrajpus malleolus Norman and Stebbing, 

 ^gawebhil (Guerin), Synldotea hicuspida (Owen), Galathura hranchiata 

 (Stimpson), Gyathura carinata (Kr0yer), vEga psora (Linngeus), Giro- 

 lana concharum (Stimpson), Idotea marina (Linnaeus), Jsera marina 

 (Fabricius), Arcturus haffini (Sabine), Girolana horealis Lilljeborg, 

 Gnathia elongata (Kr0yer), Astacilla gramdata (Sars), JEga crenulata 

 Liitken, Gryptocope arctica Hansen, Leptognathia longireiiiis (Lillje- 

 borg), Gonilera eylindricea (Montagu), Leptochelia savignyi (Kr0yer), 

 Eurxjcope cornuta (Sars), Munnopsis typica M. Sars, Jaiiira maculosa 

 Leach, Mxmna falricii Kr0yer, Mimna l-rmjeri Goodsir, Limnoria 

 lignorum (Rathke), Tanais cavoUnii MiluQ Edwards, Leptochelia duhia 

 (Kr0yer), Jxra alhifrons Leach, ^ga incisa Schicedte and Meinert, 



« Bathynomus giganieus Milne Edwards coming from the Caribbean Sea is not an 

 exception, because it is found at great depths, where the temperature of the water is 

 very low. 



^The above nomenclature was suggested by Dr. Theodore Gill for the primary 

 marine regions or realms in i^lace of the zones used by Dana. Proc. Biol. Soc. 

 "Washington, II, 1855, ijp. 1-66. 



