50 Linyiaan Societij. 



nida, and the Decapods or Crustacea, to be followed by the Myria- 

 poda, the Annelida, and the remainder of the Articiilata. 



The more important objections to this mode of arrangement are 

 considered and answered ; and the author next proceeds to examine 

 the division of the Myriapoda into tribes and genera, on which sub- 

 ject he agrees, to a considerable extent, with Professor Brandt, 

 whose plan he has followed closely in the formation of the families, 

 sections and genera, and in the characters assigned to them, but 

 whose division of the class into masticating and sucking Myi-iapodu 

 he has been unable to adopt. The following is a synoptic table of 

 the genera of the whole class : — 



Class MYRIAPODA, Leach. 



Ord. 1. CHILOPODA, Lair. — Caput latum, prominens. Corporis seg- 

 menta iiioequalia ; singula par iinicum pedum ad segmentorum latera 

 insertorum gerentia. Mandibular prominentes, acutse, falciformes. Or- 

 ganorum sexualium apertura ad extremitatem analem. 



Trih. 1. ScHizoTAiisiA, Brandt. — Antennas plun-articulatse, graciles, 

 corpore longiores. Tarsi longi, pluri-articulati, inasquales. Oculi 

 compositi, prominentes, globosi. 



Fain, 1. Cermatiidce, Leach. — Scuta dorsalia 8; singula segmenta 

 2 ventralia obtegentia. Stigmata mediana. 



Gen. 1. Cermatia, Illig. — Oculi prominentes. Caput trans- 

 versum. Scuta dorsalia emarginata. Stomatum latera in- 

 crassata. 



Trib. 2. Holotarsia, Brandt. — Tarsi 3-articulati. Caput e segmentis 

 2 mobilibus efFormatum. Antennae corpore baud longiores, setaceae 

 vel fiHforraes, 14 — 60-articidat». Oculi stemmatosi, aggregati, 

 simplices vel nuUi. 



Fam. 2. LithohiidcB, Newp. — Scuta dorsalia 15, subquadrata, in- 

 aequalia; angulis elongatis, acutis. Coxae posteriores excava- 

 tionibus ovatis. 



Gen. 2. Lithobius, Leach. — Ocelli numerosi. Caput latum, 



depressum. Labrum denticulatum. 

 Gen. 3. Henicops, Neivp. — Segmentum cephalicum latum ; 

 ocellorum pari unico. 

 Fam. 3. ScoIopendridtB, Leach. — Segmenta podophora 21 vel 23. 

 Pedes posteriores incrassati; articulo primo vel secundo spinoso. 

 Gen. 4. Scolopendra, L. — Segmentum cephalicum cordatum, 

 imbricatum. Ocellorum paria 4, Spiraculorum valvularium 

 paria 9. 

 Gen. 5. Cormocephalus, Netvp. — Segmentum cephalicum 



postice truncatum. Spiracula valvidaria. 

 Gen. 6. Rhombocephalus, Newp. — Segmentum cephalicum 



basilareque rhomboidea. Labium angustatum. 

 Gen. 7. Heterostonia, Neap. — Segmentum cephalicum trun- 

 catum. Dentes magni. Spiracula ci-ibviformia, in paribus 10. 

 Gen. 8. Scolopendropsis, Brandt. — Segmentum cephalicum 



truncatum. Pedum paria 23. 

 Gen. 9. Theatops, Netvp. — Ocelli distincti. Antennae 17- 



