250 



and different from the folded intestine, The alimentary canal is in 

 its whole length fastened to the body-wall by the dorsal mesentery. 

 The gonads are well developed and one to two times branched. 

 They enclose both eggs and sperma; the eggs are ca. 165 ^ in 

 diameter. 



The ciliated funnels (Fig. 45. 11) are found on the body-wall. 

 In the body-cavity there are found several nematods, most of which 

 are partly buried in the longitudinal muscles. 



The anchors from the posterior end of body (Fig. 45. 4) measure 

 155 // in length and 70 fi in width. They are rather slender and 

 their arms are either smooth or faintly dented. The anchors from 

 the anterior end of body (Fig. 45. 5-7) are of varying shape and 

 have always the arms quite smooth. They measure ca. 105 ^ in 

 length and 55 ,w in width. 



The shape of the anchor-plates is very varying. The plates from 

 the posterior end of body (Fig. 45. 3) measure usually ca. 105 /li 

 in length and 55 // in width, but some of them may be exceedingly 

 reduced. These reduced plates are distinctly different from the 

 various developmental stages found, and may be regarded as fully 

 developed. The plates from the anterior end of body are slightly 

 larger than those from the posterior end, measuring ca. 110 fi — 

 120 // in length and 50 [i — 65 // in width. They are more varying 

 in shape (Fig. 45. 2), but so reduced plates as in the posterior end 

 are not found. 



The miliary granules are small oval bodies, of which those from 

 the radii (Fig. 46. 9) are slightly larger than those in the interradii 

 (Fig. 45. 8). Rods are totally wanting in the tentacles, where there 

 are some rather large and oblong oval bodies (Fig. 45. 10). 



Labidoplax variabilis is distinctly characterized by the shape of 

 the calcareous ring and of the oval bodies. Probably also the shape 

 of the ciliated funnels as well as that of the anchors and plates 

 afford good characters for distinguishing it from the other species 

 of the genus. 



Protankyra 0stergren. 



0stergren. 1898. Das System der Synaptiden. pag. 116. 

 H. L. Clark. 1908. The Apodous Holothurians. pag. 97. 



The collection at hand includes only 69 specimens, representing 



8 different species, of Protankyra, the four of which are new to science. 



