107 



Astriclypeus Manni Venill.) 



I'l. [V, Fig. 1. 



This species, wiiich occurs in quile shallow water, buried in liu' sand, 

 near the Hiological Station at Misaki, was found to have ripe sexual 

 products in June (H)l 1); fertilization was undertaken on ..:;..•.■... 



the 2nd, but did not result in a good culture. After sonie 

 more unsuccessful attempts I succeeded on the 27th of 

 .Tune in gettiiit> a good culture, the larva? developing 

 normally and metamorphosing. 



The egg (Fig. 43) is surrounded by a strongly pigmented 

 mucilaginous coat. About the first developmental processes 

 I have no notices; at the age of II hours the embryos 

 were in the process of gaslrulalioii. the blastocoel being (illed with 

 mesenchyme cells; the ectoderm is thick, especially at the oral end. .\fter 

 three days the larva^ had already nearly reached the full shape, the 

 posterodorsal arms having been formed. At the age of (i days the meta- 

 morphosis was beginning, and after another week some of them had 

 completed the metamorphosis, while other specimens w-ere not yet so far 



Fig. 43. Egg of 

 Astrichipeii.s 

 Manni. »=/,. 



Fig. 44. Skeleton of the larva of Aslricli/peus Manni. ^'"/i. A. from the ventral side: 



B. .side view. Letters as in fig. 2(1. 



') In the "Preliminary Notiee on the Development of some .Japanese Kchinoderms" 

 (Annot. Zool. .lapon. VIII. Ii>l4. p. .■J47) I designated this species as "Mellila japouica". 

 having wrongly got it into my mind that there existed a Mellila japnnica: that jiaper being 

 written at sea, I had, of course, no access to litterature so that I could not then correct tlic 

 wrong idea. 



14* 



