GEODIA VARIOSPICULOSA. 



67 



As the description given above shows, these sponges arc so similar to those 

 described by Thiele as Geodia variospiculosa (Studien iiber pazifische spongien. 

 Zoologica, 1898, 24, p. 10, taf. 6, fig. 6) and variospiculosa var. clavigera (Thiele, 

 loc. cit., p. 11, taf. 6, fig. 7), which also came from Japan, that I do not hesitate 

 to assign them to this species. Still, they differ from Thiele's description and 

 also from each other in so many respects, that the question arises whether the 

 peculiarities wherein they differ are germinal in nature and systematically 

 important or merely due to differences of germ-separation or mixture before 

 and during fertilization, age, or individual adaptation to different conchtions, 

 and systematically unimportant. Thiele describes the small dermal rhabds 

 of G. variospiculosa and of G. v. var. clavigera as amphioxes, while the corre- 

 sponding spicules of the "Albatross" sponges are styles. Since, however, these 

 styles are attenuated towards both ends and consequently similar to amphioxes, 

 Thiele might easily have designated the small dermal rhabds of Geodia vario- 

 spiculosa as amphioxes even if they had exactly the same shape as the spicules 

 here described as styles. The same applies to the large subcortical ortho- 

 plagiotriaenes, which Thiele terms orthotriaenes. According to one of Thiele's 

 figures (loc. cit., taf. 6, fig. 6b) the ''orthotriaenes" of his Geodia variospicidosa 

 are orthoplagiotriaenes in my sense. Apart from these apparent rather than 

 real differences, there are, however, differences in the dimensions of the spicules, 

 many of which are very considerable. 



The specimen described by Thiele as var. clavigera is the smallest of the four. 

 The typical Geodia variospiculosa is larger, var. intermedia still larger, and var. 

 micraster by far the largest. If we were to assume that these differences in size 

 are due to differences of age, it would be only natural to suppose that correspond- 

 ing spicule-dimensions should be smallest in var. clavigera, larger in the typical 

 Geodia variospiculosa, still larger in var. intermedia, and largest in var. micraster. 

 All dimensional differences which accord with this must therefore be set aside 

 in studying the relative systematic position of these sponges. After eliminating 

 these differences possibly due to differences of age, there remain the following: 

 the large amphioxes and the rhabdomes of the orthoplagiotriaenes and the 

 dichotriaenes of the smaller var. intermedia are thicker than those of the larger 

 var. micraster. The dichotriaene-rhabdomes of the still smaller typical Geodia 

 variospiculosa are thicker than those of both the larger varieties intermedia and 

 micraster. The choanosomal tylostyles of var. intermedia have relatively larger 

 tyles than those of var. micraster. Long dermal tylostyles are present in var. 

 clavigera but absent in the three others. The mesoprotriaene-clades are rela- 



