EXPLANATION OF THE P LATHS 



Some of Ihr ligurcs o! l >phiurid-lar\ ;c \\TIT drawn 1>\ Mr. I. Li ebc rk i n (I . who has also 

 drawn sonic of the skeletal ligures of those larva' given in I ho toxl. I beg lo express here 

 my indebtedness lo Mr. I. i oli e r k i n d lor his valuable assistance. 



Plate I. 



Fig. 1. Larva of Kchiiwimlru liu-nntir (l.inn.i. two weeks old, fully formed; soon from I ho 



ventral side. Drawn from life. 15 ,. 



2. Larva of same species, same age: from the dorsal side. At I he base of the Id I postoral 

 arm is seen the beginning ainniotic imagination. Drawn from life. ' '" ',. 



Plate II. 



Fig. 1. Larva ol Tri^iiruxli'x i-xnilentux (I.esko). 17 days old; from the ventral side. Drawn 



from life. I50 / 1 . 



2. Larva of same species. 22 days old: from the dorsal side. At the base of the loll 

 postoral arm is seen a small inv agination, the amnion. A pedicollaria has begun 

 to form in a groove in the posterior end. The forward direction of the ventral ciliated 

 lobes (v. 1.) is due lo pressure of the larva under the cover. Drawn from life. lio ,. 



Plate III. 



Fig. 1. Larva of Li/li-chinux wiricyatiis (Lamk.l. l'.'> days old, seen from Iho dorsal side. 

 Drawn from life. The amnion has been formed and in the posterior end a pcdicel- 

 laria (pi is beginning to develop. '''" ,. 

 2. Larva of same species, l.~> days old, seen from the ventral side. Drawn of life. '"'" ,. 



Plate IV. 



Fig. 1. Larva of Axtriclijpciix Manni Ycrrill. li days old; seen from Iho dorsal side. am. 



amnion. Drawn from life. *'"' ,. 



2. Larva of Mcllila xt:rii'xi>rrl<>nilii (I.esko). 7 days old: seen from the dorsal side, turned 

 slighlh upwards: in beginning metamorphosis. Drawn from lite. On account of 

 the opacity of the larva the details of I he body skeleton could not be discerned 



1001 



Plate V. 



l-'ig. 1. Kmbryo of Kiu-iilurix 'riiuiiarxi (Val.i. .'! days old. -;' ,. 



2. Young larva of same species, li da\s old. slightly restored. The skeleton dissolved. 

 The small body lo the left of the month probably represents part of the enleroeoel. 



266/ 



:!. Section ol young embrxo ol I'hiilliiruiilltiix i>nn<ixi>intix Woods, in the blaslula stage. 



I. Section of embryo in the gastrnla stage ol same species. ' " ,. 



.">. Larva ol Diiiili-ma tinlilltiruni I'hil.. ."> days old: Irom the ventral side. Drawn I com 



