274 ZOOLOGY. 
mental males are degraded, imperfect forms, with sometimes 
no mouth or digestive canal. The apparent design in nature 
of their different sexual forms is to effect cross fertilization. 
The eggs pass from the ovaries into the body-cavity, where 
ma 
Ace 
sem 
Se cA 
LEE 
Fig. 223.—Anatomy of Lepas fascicularis. A. c, six pairs of legs or cirri; f, fila. 
mentary appendages ; m, mouth; s, stomach ; 4, openings of the liver (/) into the 
stomach, which tebe eeuted as laid open; i, intestine; a, vent ; ¢, testis ; v, vasa 
-deferentia, one cut off ; p, male appendage ; 0, ovary ; e¢, adductor muscle eonnenting 
.the two, basal valves; vs, scutal valve; ve, carinal valve ; v2, tergal valve. Enlarge 
twice. 
B. 1, palpus; 2, mandibles ; 3 and 4, first and second maxille. 
G. Nervous system. s, brain, sending the optic nerves to the rudimentary eye (¢), 
each optic nerve having an enlargement near the eye, i. ¢., the ophthalmic ganglion (0); 
between o and a@ are the nerves which go to the peduncle; a, nerve sent to the ad- 
ductor sculorum ; @, commissure between the supra- and infraesopha eal ganglia (7) ;° 
£, €, ¢, 6, €, &, nerves to each of the six feet, Enlarged four times,—After gsley. 
they are fertilized, and remain for some time. They pass 
through a morula condition, a suppressed gastrula or two- 
Jayered state, and hatch in a form called a Nauplius, from 
the fact that the free-swimming larva of the Entomostraca 
