62 



GEODIA VARIOSPICULOSA. 



The mesoproclades observed were nearly all mesoprotriaenes. I found only 

 a single mesopromonaene. 



In the mesoprotriaenes (Plate 17, fig. 32) the epirhabd is straight, conical, 

 and usually shorter than the clades. The latter are conic, pointed, and curved, 

 concave to the epirhabd. Their curvature increases distally. This cUstal 

 increase of curvature is most marked in the mesoprotriaenes with strongly 

 diverging clades (large clade-epirhabd angles). In the preparations of var. 

 micraster no intact mesoprotriaene-rhabdomes were found, so that I can not state 

 their length. The thickness of the rhabclome at the cladome is 7-20 /i; the 

 epirhabd is 25-90 /< long; the clade-chords are 40-140 /< long and enclose angles 

 of 30-63° with the axis of the epirhabd. In var. intermedia the rhabdomes of 

 these spicules are 2.9-3.2 mm. long and at the cladome 18-23 /< thick. The 

 epirhabd is 60-75 n long; the clade-chords are 100-142 pi long and enclose angles 

 of 37-44° with the axis of the epirhabd. 



Besides these normal mesoprotriaenes a few with one or two stunted 

 cylindrical clades, rounded off at the end, have been observed. One of these is 

 represented in Plate 17, fig. 32. 



In the preparations of var. micraster I found one mesopromonaene with a 

 broken rhabdome, 30 ^ thick at the cladome. Its epirhabd is 180 n long, its 

 clade is recurved in a hook-like manner at the end and slightly concave to the 

 epirhabd. The clade-chord is 175 /i long and encloses an angle of 35° with the 

 axis of the epirhabd. 



The large anatriaenes (Plate 17, figs. 23-31; Plate 18, fig. 8d), when fully 

 and normally developed, have a long rhabdome, thickened towards the cladome, 

 and three fairly equal, conical and uniformly curved, pointed clades (Plate 17, 

 figs. 25, 26, 29, 30). Sometimes the clades are bent down abruptly at their 

 ends (Plate 17, fig. 27). The apex of the cladome is simply rounded or, more 

 rarely, crowned by a very slight protuberance. In var. micraster the rhabdome 

 is 3.6-5.2 mm. long and at the cladome 20-46 /n thick. The clade-chords are 

 65-130 long and enclose angles of 37°-70° with the axis of the rhabdome. 

 In var. intermedia I found only one intact rhabdome, 4.2 mm. in length. In 

 this variety the rhabdomes are 20-40 n thick at the cladome and the clade- 

 chords 50-135 long. The clade-rhabdome angle is considerably smaller than 

 in the other variety, measuring only 35-48°. 



Besides these normal large anatriaenes four other, abnormal or derivate 

 forms are observed: 1, regular anatriaenes with pointed clades but of much 

 smaller dimensions; 2, irregular anatriaenes of normal dimensions and clade- 



