MONOGRAPH OF JAPANESE OPHIUROIDEA. 83 



finely and closely granulated, the grannies being very irregular in 

 size and roughly distinguishable into two kinds. The fi.ner granules 

 are entirely covered over by the skin, and are flat and irregularly 

 polygonal, forming together a sort of mosaic ; while the coarser 

 granules, which are coarser than any granules of the disk, are 

 hemispherical and tubercle-like, and are uniformly scattered. Ventral 

 surface of arms apparently smooth,' but really covered by a mosaic 

 of flat and irregularly polygonal granules of microscopic size. The 

 first pair of tentacle pores are distinct and open in slight depres- 

 sions. The second are often visible. The following three or four 

 pairs are entirely absent, those beyond being again distinct. The 

 arm spines are entirely absent in the proximal joints, but are 

 present from the fourth or fifth bifurcation outwards. They are 

 exceedingly minute and granule-like, two to four of them occurring 

 for each tentacle pore. The double rows of hook-bearing granules 

 are present only in very fine twigs, the main stems within the 

 fourteenth or fifteenth bifurcation being free of them. The shaft 

 between the first and second bifurcations usually contains four 

 arm joints. The outer shafts are composed of from six to eight, 

 usually seven, joints. 



Colour in alcohol, as well as in a dry state ; dark grayish 

 brown above, and dark yellowish brown below. ... 



Of the five known species of Astrohoa, A. clavata (Lyman) is 

 distinguished from the others by the spiny granules of the disk 

 and arms, and A. globifera (Döderlein) by the position of the 

 madreporic shield. A. mida (Lyivian) and A. nigra Dödeelein have 

 distinct annulations of hook-bearing granules on the arms, while 

 A. ernce Döderlein has no such annulation on the greater proximal 

 parts of the arms. This species is therefore very near to the 

 last named but differs from it in the less distinct and much finer 



