CHAPTER VI 



CRUSTACEA {CONTINUHD) EUMALACOSTEACA {CONTINUED) : 



EUCARIDA EUPHAUSIACEA COMPOUND EYES DECAPODA 



DIVISION 4. EUCAEIDA. 



The carapace fuses with all the thoracic segments. The eyes 

 are pedunculate. The mandible is without a lacinia mobilis. 

 There are no oostegites, the eggs being attached to the endo- 

 podites of the pleopods. The hepatic caeca are much ramified, 

 the heart is abbreviated and saccular, the spermatozoa are 

 spherical with radiating pseudopodia, and development is typically 

 attended by a complicated larval metamorphosis. 



Order I. Euphausiacea. 



The Euphausiidae ^ agree with the Decapoda in passing 

 through a complicated larval metamorphosis. The young hatch 



out as ISTauplii, with 

 uniramous first an- 

 tennae and biram- 

 ous second antennae 

 and mandibles. In 

 the next stage, or 

 " Calyptopis " (Fig. 

 101), which corre- 

 sponds exactly to 

 the Zoaea of the 

 Decapoda, two pairs 

 of maxillae and a 

 pair of hiramous inaxillipedes are added ; the hinder thoracic 

 segments are undifferentiated, but tlie abdomen is fully segmented, 



' Sars, Clin.Uciiger Reports, xiii., 1885 ; Chun, Bibliotheca Zoologica, xix., 1896, \i. 139. 



144 



Fig. 101. — Qn\y])to'^\sla,rYa, ai Euphausiapdlucida, x about 

 20. A.l, 1st antenna; Ab.6, 6tli abdominal segment; 

 E, eye ; 3f, maxillipede. (After Sars.) 



