THE CIRRI FED I A 



127 



ventral side of the alimentary canal. The nervous system is 

 reduced. An eye is stated to be present in Synagoga. In Laura 

 the oviducts open at the base of the first pair of cirri. In the 

 other genera they have not been traced. Petrarca is hermaphrodite, 

 and the vasa deferentia open on a large penis which terminates 

 the body. In Laura the testes are described as lodged in the 

 bases of the second, third, fourth, and fifth cirri, opening to the 

 exterior by numerous fine ducts, but this account is open to doubt. 

 Dwarf males have recently been described in Dendrogaster. 



B 



Fio. 77. 



Laura gerardiae. A, body exposed by removal of one-half of the mantle, ant, antenna ; 

 F, hepatic diverticula ; /, caudal furca ; g.s, cerebral ganglion ; i, intestine ; o, opening of 

 mantle ; ov, ovary ; o. $ , opening of oviduct ; o. , opening of male ducts ; sac, wall of mantle. 

 B, one of the papillae of the mantle, fi, vascular filaments ; v, blood-vessel. (After Lacaze- 

 Duthiers, from Gravel's Monographic.) 



A nauplius larva peculiar among the Cirripedia in lacking the 

 fronto-lateral horns of the carapace has been observed in Laura. 

 In Dendrogaster the nauplius stage is suppressed and the larva 

 hatches as a peculiar Cypris larva (Fig. 78, C), with only five 

 pairs of biramous thoracic limbs, a long abdomen of five somites, 

 stout antennules with hooks, and a very large olfactory filament 

 (aesthetasc). There are no eyes, and the gut already sends a 

 diverticulum into each valve of the shell. 



