1390 CRUSTACEA. 



ARACHNIDA. PYGNOGONOIDEA. 



2. Mandibles. f Trunk corresponding to 1, man- 



2. Maxillae-. \ dibles, and 2, maxillae. 



3. Labium or second maxillae. 3. Ovigerous legs. 



4. 5, 6, 7. Legs. 4, 5, 6, 7. Legs. 



Internal Structure. — Upon this subject, we enter into no discussions 

 simply referring to our figure 2, Plate 96, made February, 1842 (and 

 therefore, before having seen the researches by Quatrefages, which 

 were published in 1844). It represents the alimentary cavity as a 

 tube running the length of the body, and sending a branch into each 

 leg to its extremity, besides two branches into the trunk. 



Arrangement of the Pycnogonoidea. 



Fam. I. NtMPHIDJSr. 



Antennae elongatae, 1-2-rameae. 



G. 1. Nymphum, Fair* — Antennae birameae, ramo crassiore chelato, altero 5-arti- 

 culato. Truncus ad basin vix angustior. Abdomen uni-articulatum. 



G. 2. Ammothea, Leach. — Nympho affinis. Ramus antennae longior 9-articulatus. 



G-. 3. Zetes, Kr'6yer.\ — Antennae birameae, ramis gracilibus. Truncus ad basin 

 multo angustior. Abdomen 2-articulatum. 



G-. 4. Pallene, Johnston. — Antennae unirameae, chelatae, sat crassae. Abdomen 

 1-articulatum. Pedes lmi (ovigeri) 11-articulati. 



G. 5. Phoxichilldium, Edw.% — Pallene affinis. Pedes lmi (ovigeri) 5-articulati. 



G. 6. Pasithoe, Goodsir.§ — Antennae unirameae, non chelatae, graciles. 



Fam. II. PYCNOGONIDiE.. 

 Antennae nullae. 



G-. 1. Pycnogonum, Brunnich. — Pedes breves. Pedes ovigeri 10-11-articulati. 

 G. 2. Phoxichilus, Latr. — Pedes praelongi, gracillimi. 



* Pephredo, H. D. S. Goodsir, Jameson's J., xxxii. 13T. 



t Tidsskr. [2], i. J Orythia, Johnston, Mag. Zool. Bot., i. 378. 



§ Jameson's Jour., xxxiii. 367. 



