NOTES ON APHROCALLISTES BEATRIX GRAY. 



179- 



in numerical proportion of occurrence, is readily distinguishable from this 

 in having distinctly thicker shaft and terminal branches, which latter 

 usually number four, stand out nearly parallel with one another or diverge 

 but very little, and are scarcely or but indistinctly swollen at the tip. 

 Moreover, both the shaft and the branches are very minutely and fairly 

 uniformly tubercled all over. In length the pachyscopule is about equal 

 to, or somewhat longer than, the leptoscopule in the same stock. 



The hexasters are exceedingly variable as regards their characters as 

 well as in number, and in case they occur in more than one distinguishable 

 varieties, in the numerical proportion of these also. The variation refers 

 not only to different stocks, but also in a measure to different parts of one 

 and the same stock. The hexaster varieties to be ascribed to A. bcatrix 

 orieiitalis as a whole are both discohexaster and oxyhexaster, each of 

 which may again be divided into a regularly developed (" synstigme ") 

 form and an elongate hemihexasterous (" syngramme " form), thus giving 

 in all four varieties of hexasters. Not necessarily all the four occur together 

 in the same stock ; but any one or two or even three of them may be 

 found to be missing in spite of careful searches. In twelve Japanese 

 specimens which I have studied with special care as regards their hexasters, 

 the four varieties were found distributed in the manner indicated in the 

 following table. 



Number of 

 specimens 

 examined 



A 



Regular disco- 

 hexaster 



B 



Regular oxy- 

 hexaster 



c 



Elongate hemi- 

 discohexaster 



D 



Elongate hemi- 

 oxyhexaster 



6 



+ 



+ 



+ 



+ 



2 



+ 



+ 



o 



+ 



I 



+ 



o 



o 



+ 



I 



+ 



o 



+ 



o 



I 



+ 



o 



o 



o 



I 



o 



o 



+ 



o 



+ denotes presence, and O apparent absence, of the hexaster variety they relate to. 



