10 POSSIL ESTHERIJE. 



Some remarks on that subclass of the Crustacea known as Entomostraca have been 

 made in my former Monographs on the Cretaceous and Tertiary Ostracoda (1849 and 

 1856) ; and, to show the place of Estheria in the Crustacean group, Mr. J. D. Dana's 

 classification' is here produced. 



CZ^^S-.— CRUSTACEA. 



Subclass I. Dbcapoda. II. Teteadecapoda. III. Entomostraca. 

 Subclass. — Entomostraca. 



Ordo I. Gnathostomata. 



Legion I. Lophyropoda. 



Tribus I. Cyclopoidea. 



Fam. I. Calamidae. II. Cyclopoidse. III. Corycoeidse. 

 Tribus II. Daplinioidea. 



Fam. I. Penilidse, II. Daphnidse. III. Polyphemidae. 

 Tribus III. Cyproidea. 



Fam. I. Cypridse. 



Subfam. I. Cyprinse (Cypris, Candona). ^ II. Cytherinse. 

 {Cy there). 

 Fam. II. Halocypridse. 



Subfam. I. Cypridininse. II. Halocyprinse. 

 Legion 11. Phyllopoda. 



Tribus I. Artemioidea. 



Fam. I. Artemiadae. II. Nebaliadse. 

 Tribus II. Apodoidea. 



Fam. Apodidse. (Apus). 

 Tribus III. Limnadioidea. 



Fam. Limiiadidse.2 



Genus 1. Limnadia, Ad. Brongniart. 



2. Cyzicas, Audouin. [Estheria, Riippell.] 



3. Limnetis, Loven {Hedessa, Lievin). 

 Ordo II. Cormostomata. 



Subordo I. Poecilopoda. II. Pycnogonoidea (vel Arachnopoda). 



Limnadia has the following diagnosis : — " Caput vix rostriforme, dorso tuberculum 

 pyriforme gerente. Pedes toti foliacei. Abdomen extremitate appendicibus acuminatis 

 quatuor armatum." 



Cyzicm^ \Estheria, Riippell and Straus-Durckheim]. " Caput instar rostri productum, 



^ ' Report on Crustacea of the United States' Exploring Expedition,' 1853, pp. 1277, &c. 



2 Apusiens (in part) of Milne-Edwards, ' Hist. Nat. Crust., iii, p. 513. 



^ Audouin, 'Ann. de la Soc. Entom.,' vol. vi, 'Bullet.,' Feb., 1837, p. ix; Estheria, Riippell and 

 Straus-Durckheim, 'Mus. Senckenberg.' ii, 119, 1837 ; Isaura, Joly, 'Ann. Sc. Nat.,' 2 ser. xvii, p. 293, 

 1842. 



Dr. Baird has the following observations on the generic name of this animal : " This genus was indi- 



