211 
gradually diminishing in size, until beyond the second forking they 
disappear. The arm spines are short, thick, skinclad, with the 
point somewhat thorny. They are arranged in transversal rows, 
five in number in the larger basal part of the arm. On the joiuts 
contained in the disk (7) their number is somewhat inconstant, 
sometimes only 4, or even 2; on the. second joint there are only 
2—3, on the first joint none. From the second forking the number 
of the arm spines diminishes, until at the outer branches there is 
only one; contemporaneously they become more slender, but they 
are not transformed into hooks. 
" Ås in A. propugnatoris the arms widen from the mouth 
towards the edge of the disk, from there diminishing in width very 
gradually outwards. The arms are somewhat unequally developed, 
both as regards their size and the distances between the forkings, 
as seen from the measurements of two arms given here: 
Årm ÅA. Arm B. 
Length from base to 1. forking ... 75 mm. 95 mm. 
snes ae l. - 2. — ... 40—42 — 33 — 
me en 2. - 8. — ... 14—58 — 40—15 — 
These measurements also indicate that the two branches of a 
forking are mostly of very unequal length. 
The skin covering the upper side of the disk and the arms 
is of a brownish colour which makes the large white tubercles the 
more prominent. 
The specimen was taken at lat. 32? 20' N., long. 1282 15' E.; 
110 fathoms; bottom temperature 11,1? (52? F.). 17. V. 1911. It 
Was, unfortunately somewhat damaged, two of the arms being 
broken a little inside the first forking and another arm being 
broken within the disk, but remaining attached by the dorsal skin. 
Also the specimen of A. propugnatoris was somewhat similarly 
damaged. It thus appears that the species of this genus are rather 
fragile in spite of their stoutness. 
14” 
