Larx:ol Stinjes of Triloblfes. — Betclicr. 195 
Figure 9. DahnaniteH socialis Barrande ; after Barrande. Meta- 
protaspis stage : showing the stronger definition of the pleura of the 
pygidium. x30. Ordovician, Bohemia. 
Figure 10. Dalmauiles snciali.s Barrande ; after Barrande. The 
specimen probably represents the close of the paraprotaspis stage, and 
shows four segments in the pygidium and the first evidence of the 
backward movement of the eyes, which now indent the margin. x.30. 
Ordovician, Bohemia. 
Figure 11. Dalmanltes socialis Barrande ; after Barrande. Outline 
of an adult individual, x^-y. Ordovician, Bohemia. 
PLATE X. 
The Roman numerals indicate the appendages in their consecutive 
order. 
I, 1st pair of appendages, or antennules. 
II, 2d pair of appendages, or antennae. 
III, 3d pair of appendages, or mandibles. 
IV, V, etc., maxillae, maxillipeds, swimming feet, etc. 
Oct, unpaired eye : oc, paired eyes; lb, labrum. 
Figure 1. Triarthnis becki. A restoration of the ventral side of the 
protaspis stage in accordance with the best evidence at present attain- 
able, as explained in the text. The Vlth and the Vllth pairs of ajj- 
pendages belong to the abdomen, which is marked off by a transverse 
line : mi, metastoma : g. free-cheeks. 
Figure 2. Apus cane rif or mis : after Claus (from Faxon). Phyllo- 
poda. Nauplius larva, just hatched : ventral side. Behind the mandi- 
bles (III) are indications of five thoracic somites, y. 
Figure 3. Apus cancriformis ; after Claus (from Faxon). Phyllo- 
poda. Second larval stage (metanauplius); ventral side. The second max- 
illa, V, is wanting : /, frontal sense organs. 
FuiURE 4. BranchipHH starjiidJis : after Claus (from Packard). 
Phyllopoda. Nauplius stage. 
Figures. Artemia gracilis: after Packard. PhyllofuKia. Nauplius 
stage; showing obscure segmentation. 
Figure 6. Limnaida hermatiM: after Lereboullet (from Packard). 
Phyllopoda. Nauplius : dorsal side : first pair of appendages obsoles- 
cent: labrum, lb, greatly developed. 
Figure 7. Lepidurus productii.H; after Brauer (from Bernard). 
PliyUopoda. Nauplius with obscure segmentation of the trunk, y. 
Figure 8. Leptodara liyaliiia : after Sars (from Balfour and Broun). 
Phyllopoda, Cladoccva. Nauplius larva from winter egg: //, rudimen 
tary feet. 
FiciURE 9. Daphnia loHgispina; after Dohrn (from Claus). PItyllo 
jioda, Cladocera. Naujjlius stage of embryo, with rudimentary append 
ages. 
Figure 10. Moina rectirostris ; after GrobVjen (from Fa.xon). Phyllo- 
poda, Cladocera. Embryo from the summer egg in the nauplius 
stage, developed in the brood-cavity of the parent: appendages rudi 
mentary. 
