PLATE V 



CRUSTACEAN LAKV.E (Pages 191, 192) 



The Roman numerals indicate the ap[ieudagcs in their consecutive 

 order. 



/, 1st pair of appendages, or antennules. 

 //, 2d pair of appendages, or antennaj. 



in, oil pair of appendages, or mandibles, 



IV, V, etc., maxilla:', nnixillipcds, swimming feet, etc. 



ocl, unpaired c^ve ; oc, jiaired eyes; lb, labrnm. 



I'iGURK 1. — J'ri(ii-l/irus Becki. A resti>iati(ju of the ventral side of 

 the protaspis stage in accordance with the best evidence at present at- 

 tainable, as explained in the text. The K/th and the l'//th pairs of ap- 

 pendages belong to the aljdomen, which is marked off by a transverse 

 line; m/, metastoma; r/, fiee-dieeks. 



FlGUUK 2. — Aims ciincriJhrmiK (After Claus, from Faxon.) Phyllop- 

 oda. Xaniilius larva, just hatched; ventral side. Behind the mandibles 

 {III) are indications of five thoracic somites (//). 



FiGiTRE :!. — Ajius ctiiicrifonnis. (After Claus, from Faxon.) Phyllop- 

 oda. Second larval stagi' (metanauplius) ; ventral side. The second 

 maxilla ( V) is wanting; /; frontal .sense organs. 



Figure 4. — Br(inc/iij/us slagnalis. (After Claus, from Packard.) 

 Phyllopuda. Nauplius stage. 



Figure -5. — Arteinin t/racitis. (.\fter Packard.) Phyllopoda. Nau- 

 plius stage ; showing ojj.scure segmentation. 



Figure 6. — Limnniilu lleimanni. (.Viler Lerebonllet, from Packard.) 

 Phyllopoda. Nauplins; dorsal side; tirst pair of appendages obsoles- 

 cent ; labrnm (lb) greatly develojieil. 



Figure 7. — Lcpiiluras productus. (After Braiier, from Bernard.) 

 Phyllojioda. Xauplius with ob.scure segmentation of the trunk (y). 



Figure 8. — LepUxUini hijalinn. (After Sars, from lialfour and Bronn.) 

 Phyllopoda, Cladoeeia. Nauplius larva from winter egg ; y, rudimentaiy 

 feet. 



Figure f). — Bajjlmiti loiif/ispimi. (After Dohrn, from Claus.) Phyllop- 

 oda, Cladocera. Nauplins stage of embryo, with rudimentary append- 

 ages. 



Figure 10. — Muinti reclirosiris. (After Grobben, from Faxon). Phyl- 

 lopoda, Cladocera. Embryo from the summer egg in the naujilius stage, 

 developed in the brood-cavity of the parent ; appendages rudimentary. 



Figure 11. — Cyrlnjjs leinticnrnis. (After Claus, from Baltonr.) Co- 

 pepoda, Xatantia. Nauplius, first stag(;. This and the next are the 

 original forms de.scribed as Nauplius, by (). F. Miiller, and believed at 

 that time to be adult. 



Figure 12. — Cyclops tenuicornis. (After Claus, from Balfour.) Co- 

 pepoda, Natantia. Nauplius; .second stage ; / T, maxilla3. 



