212 GEODINELLA UOBUSTA. 



former had a diameter of 50 n and the part of the spicule from which it arose 

 was 42 fi thick. The latter had a diameter of 43 /( and the part of the spicule 

 from which it arose was 40 // thick. Occasionally, but very rarely, rhabds with 

 a clade-shaped protuberance, resembling anamonaenes (Plate 4, fig;. 10) occur. 



In the rhabds with undulating surface the irregularity is probably caused 

 ])y some inequality in the action of the silicol)lasts during growth. The monaene- 

 like forms just referred to are altogether abnormal, proliably pathological. The 

 rhabds with tlie rounded and annular protuberances I am inclined to consider 

 as spicules transitional between regular rhabds and teloclades. 



The teloclades and teloclade-derivates (Plate 1, figs. 1-11, 13-15, 18-20; 

 Plate 4, figs. 23, 25). The cladome of the telcjclades is always reduced. This 

 reduction is different in degree and in kind in the three varieties. In var. 

 carolae the teloclades have entirely lost one or two of the triaene-clades ; in the 

 two others invariably two. In var. mcgadada the single remaining clade is often 

 quite long. In the two other varieties the clades are always very short. Thus 

 var. carolae possesses some diaenes besides the monaenes, both with short 

 clades, var. megaclada only monaenes, many of which have a rather long clade, 

 and var. megasterra only monaenes, which always have a short clade. In all 

 three the cladome is usually simple and situated at or near the cladomal end 

 of the rhabdome. Besides tliese ordinary teloclades, teloclade-derivates with 

 more cladomes than one, and with clades arising some distance from the end 

 or reduced to insignificant protuberances, are met with. 



The diaenes and monaenes of var. carolae (Plate 1, figs. 5-11) have the 

 same dimensions. The monaenes (Figs. 6, 9-11) are much more numerous 

 than the diaenes (Figs. 5, 7, 8), particularly in the specimen from Naha Bay. 

 The rhabdome is 1.1-1.7 mm. long and at the clatlomal enil 26-40 /i thick; 

 it is generally straight or slightly curved, rarely (Fig. 6) angularly bent, and 

 usually attenuated towards the acladomal, blunt or, more rarely, pointetl end. 

 Sometimes (Fig. 5) this attenuation is so slight that the rhabdome appears 

 nearly cylindrical. In such spicules it is simply roumled off at the end. The 

 cladome is generally quite terminal (Figs. 5-9, 11), rarely situated a little below 

 the end of the rhabdome (Fig. 10). The clades are 30-70 /(, usually 40-55 /< long, 

 generally quite straight, irregularly conical, and pointed (Figs. 5, 6, 8-10), 

 or, more rarely, cylindrical and rounded terminally (Fig. 11). In the diaenes 

 a pointed clade may be associated with a rounded one (Fig. 7). The clades 

 enclose angles of 93-130° with the rhabdome, so that some of these spicules ap- 

 pear as orthodiaenes or orthomonaenes (Fig. 10), others as plagio- or pro-diaenes 



