298 L» Agassiz on the Echinodermata. 



arc however not yet well enough based to be admitted without re- 

 serve. Several of them I have not had occasion to examine myself. 



1. Synapta, Esch. (Putularia, De Bl. — TUdemannia, Lcuck. — 

 Holothuria, De HI. Beet. D.)— Body vermiform, presenting no differ- 

 ence between the upper and under surface; epidermis delicate ; the 

 mouth surrounded by large pinnatifid tentacula. Tubercles, for the 

 most part crooked, and serve as feet, although the animal is not en- 

 tirely destitute of vascular tubes. 



S. Beseliu Jag. — S. oceanica, Less. — S. mammillosa ; Esch. — S. viltata, 

 Jseg.—CTiedemannia vitt., Leuck.)—S. reciprocal, Jaeg. — (Fistularia, rc- 

 cipr., Forsk. — Holothuria glutinosa, Lam.) — S. maculata, Jseg. (Hoi. mac, 

 Cham.)—S. radlosa, Jseg. (Hoi. rad., Regn.) — S. inhcerens, Wieg. (Hoi. inh., 



Mull.) 



2. Chirodota, Esch. — Epidermis thin, rather thicker however 



than in Synapta, beset with a small number of feet or merely of re- 

 tractile mammilla?. Tentacula digitate. 



Ch. purpurea, Less. — Ch. lumbricus, Esch. — Ch. verrucosa, Esch. — Ch. 

 discolor, Esch. 



3. Thyone, Oken. (Mulleria, Flem.) This genus differs from the 

 preceding solely in having the entire body covered with retractile 



papillae. 



Th. papillosa (H. papill., Mull.), — Th. fusus (H. fus., Mull.). — Th. im- 

 patiens (B. imp., Forsk.). — Th. maculata (Hoi. mac, Le S.). — Th. Briar eus 

 (Hoi. Br., Le S.). — Th. lapidifera (H. lapid., Le S.). — Th. peruviana (H. 

 peruv., Le <S".). 



4. Trepang, Jaeg. — Body subcylindrical ; mouth anterior, sur- 

 rounded by ten to twenty tentacula in a peltate head ; feet confined 

 to the belly. This genus is doubtful, and ought probably to be 

 united to the Holothuriae properly so called. 



T. edulis (Hoi. edul., Less.). — T. ananas, Jseg. 



5. Holothuria, Linn. ; DeBl. sect. B. {Fistularia, Lam.) — Body 

 subcylindrical, anus rounded ; mouth subinferior. Retractile tubes 

 developed, especially under the belly. 



H. tubulosa, Linn. — //. columnce, Cuv. — H. maxima, Forsk. — H. elegans, 

 Mull. — H. Forskalii, Delle Ch. — H. Petagnii, Delle Ch. — //. Sanctorii, 

 Delle Ch.— H. Cavolinii, Delle C\\.—H. Polii, Delle Ch.— H. Stellati, 

 Delle Ch. — 7/. Dismarii, Cuv. — H. appendiculata, De Bl. — //. radackensis, 

 Cham. — H. brunnea, Cham. — H. aggluiinata, Le S. — H.umbrina, Rupp. et 

 Leuk. — H. quadrangularis, Less. — H. fusco-cinerea, Jseg. — H. atra, Jseg. — 

 H. fusco-punctata, Jseg. — H. lilla, Less. — H. scabra, Jteg. — H. monacaria, 

 Less. 



6. Mulleria, Jaeg. — Back convex; belly flat ; skin coriaceous; 

 twenty tentacula peltate and disposed in two series round the mouth ; 



