54 



al 



Temnotrema sculpta A. Ag. 



PI. VI, Fig. 4. 



This species, which occurs -- though in rather small numbers -- under 

 stones or among Laminaria-roots along the shores at Misaki, was found 

 to be ripe in the end of April. Fertilization was undertaken on the 26th 

 and later on again in the end of May, 1914. The cultures were not quite 

 as good as desirable, and the larva? could not be reared till the full shape 

 was reached; still valuable information was obtained, showing that the 



shape and structure of this larva is in conformity 

 with that of the other Temnopleurid-larva? here 

 described. 



The eggs are very small, and the first develop- 

 mental processes occupy a very short time only. 

 The embryos were found to have assumed the shape 

 of young Plutei at the age of 36 hours (probably it 

 does not really take so long time to reach that stage). 

 The shape of the young Pluteus is very much like 

 thai of Temnopleums toreumaticus; the body is 

 elongate on account of the long body rods; the ven- 

 tral side of the body is distinctly concave. The 

 stomach, oesophagus and rectum are small but 

 hardly so small as in Temnopleums toreumaticus ; 

 the anterior border of the oral lobe is thickened as 

 in that larva. The skeleton (Fig. 17) is of the same 



Hg. I/. Skeleton ol larva 



of Temnotrema sculpta. type as in the Temnopl. loreumaticus-larva; the 

 2V 2 days old; side view. bodv ro( } is elongate, thornv, ending in two or 



300 / Letters as in fig 5 



three horizontal branches; the recurrent rod is 



quite small, curved; no basket structure is formed. The postoral rod is 

 fenestrated. 



The most advanced stage reached is that figured in PI. VI, Fig. 4, 

 from a larva 18 days old; the arms are broad, rather abruptly narrowing 

 towards the point; the posterodorsal arms have appeared, but not the 

 preoral ones. The postoral ciliated band bends somewhat downwards 

 in the middle, and the anal area is slightly concave here. Along the sides 

 of the body the ciliated band goes far downwards which indicates 

 that postero-lateral lobes will develop as in the Mespilia-larva. Con- 

 spicuous red pigment cells are distributed along the vibratile band and over 

 the body; in the point of the arms a few pigment cells occur. - - Vibratile 

 epaulets have not been formed. 



In the larva figured the body rods had begun to be absorbed, but no 



