l',)(j Tlie Americtiii (icohnjisf. Soptemhor, l.s9r) 
FitiL'Kp; 11. ('nvlopa teitniconiis ; liiUn- Wdun (fnnn Balfour). Cope- 
poda, Natantiu. Nauplius, first stage. This and the next are the origi- 
nal forms described as Na}(plinH, by O. F. Miiller, and believed at that 
time to be advilt. 
Figure 12. Ciiclopa tciiidconiis : after Glaus (from Balfour). Cope- 
poda, Nato.nti((. Nauplivis, second stage: IV, maxillia?. 
FiGUKE 13. CetocJitlKs sepfentrionaJis : after Grobben (from Faxon). 
(Uypepoda, Nntaniia. Naviplius, just hatched : ventral view. 
Figure 14. ArJiilieres percarum : after Claus (from Faxon). Cope- 
poda. Parasitica. Larva at the time it leaves the egg, with only two an 
terior unbranched pairs of appendages of the typical nauplius present. 
Under the skin are the rudiments of six pairs of appendages : III, man- 
dibles ; IV, maxillae : V, VI, maxillae : VII, VIII, swimming feet. 
Figure 15. Balaniis Itahoioides : Httev Hoek (from Faxon). Cirri- 
pedia. Nauplius. 
Figure 16. LerncediseuH porcellaiav : after F. Miiller (from Faxon). 
Ciryipedia, Rhizoce})haJa. Nauplius, ventral side: showing outline of 
dorsal shield. 
Figure 17. Sacciiliiia purpurea : after F. Miiller (from Huxley and 
Balfour). Cirripedia, Rhizocephala. 
Figure 18. Cijpris ovum: after Claus (from Faxon). Ontracoda. 
First larval (nauplius) stage, with bivalve shell and unbranched second 
and third pairs of appendages. 
Figure 19. Nebalia geoffroyi : after Metschnikoff (from Faxon). 
Lepfostraca. Side view of the so-called nauplius stage of the embryo 
within the egg. Rudiments are present of the two pairs of antennie, I, 
II, the mandibles, III. 
Figure 20. Eiipliansia : after Metschnikoff" (from Faxon). Scin'zo- 
poda. Nauplius, just hatched. 
Figure 21. Euphauaia: after Metschnikotf (from Faxon). Schizo- 
poda.. Nauplius at a later stage : ventral view : int, metastoma; IV, V, 
maxilla?; VI, maxilliped. In the next, or Protozoen, stage, the append- 
ages, IV, V, VI, are true phyllopodiform feet. 
Figure 22. Mysis fcrruginea : after Van Beneden (from Faxon). 
Sehizopoda. Nauplius like embryo: side view. The appendages are 
unsegmented, and the third pair quite rudimentary. A number of later 
metamorphoses are undergone in the nauplius skin, until the full num 
ber of appendages is developed. 
Figure 23. Pphcj^.s; after F. Miiller (from Faxon). Decapoda. Mac- 
roura. Nauplius : fron\ dorsal side. 
Figure 24. Lucifer : after Brooks (from Faxon). Decapoda , Macron va . 
Ventral view of embryo artificially removed from the egg : IV, V, VI, 
buds representing the two pairs of maxilla- and first pair of maxillipeds 
of the adult. 
Figure 25. Pala'uioii : after Bobretzky (from Faxcm). Decapoda, 
Macronra. Nauplius stage of embryo within the egg. 
Fkjure 26. AxtaciiH fluriaiilia: after Reichenbach (from Faxon). 
Decapoda, Macronra. Nauplius stage of embryo. 
