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forms are very easily distinguished, mainly through the quite differ- 
ent shape of the oral shields, which are distinctly rhomboidal 
equally long and wide, in O. fasciata, whilst in O. Schayeri they 
are elongate, egg-shaped, with the outer edge truncate, and distinctly 
longer than broad. This difference is quite constant, and equally 
distinet in younger and adult specimens. Further the dorsal plates 
are distinctly broader in Schayeri than in fasciata, the distal edge 
being twice the width of the supplementary plates in the Australian, 
only equalling the width of the supplementary plates in the New 
Zealand species. Also another feature appears to represent a val- 
uable distinguishing character. In the New Zealand form the edge 
of the genital slits, especially at the inner end, bends outwards 
and looks like a sort of web, being more conspieuous on account 
of its white colour. There is a distinet row of small papillæ along 
the edge; sometimes the papillæ continue so far dorsally along 
the base of the arm as to get the appearance of an armcomb. The 
‘‘webs“ from the two genital slits in each interradial space almost 
meet in the midline outside the oral shield. In O. Schayeri and 
other species of this genus, this “web“ is mueh less distinet and 
a wide space separates the two slits outside the oral shield. The 
shape of the ventral plates would appear from the two figures to 
differ rather considerably in the two forms; I do not, however, 
find the difference sufficiently constant for forming a reliable di¬ 
stinguishing character. The same holds good for the small inner 
tentacle scale seen in the figure of O. Schayeri. It is true, I have 
never observed this small scale in the New Zealand species, but, 
on the other hånd, I have not found it constantly in the Australian 
form — perhaps its lacking in some specimens is due to bad pre- 
servation; but for the present, I do not venture to lay any stress 
on this feature as a distinguishing character. The scales of the 
interradia on the ventral side are somewhat larger in the Australian 
than in the New Zealand form, and also the proximal part of the 
interradia is more naked in the former than in the latter form; 
small spines are found on the proximal part of the interradia in 
both forms. 
The differences here pointed out leave no doubt that the New 
Zealand form is a distinet species, not identical with the Australian 
form. The type specimen of Muller and Troschel’s Ophiolepis 
