62 
bulletin of the bureau of fisheries. 
A specimen taken at Nagasaki by Lischke has been figured by Hoek. The same author has 
described a variety robusta from the Malay Archipelago. This form has a broader capitulum and is 
said to have a longer peduncle. In the latter character, at least, the Japanese form does not differ 
from the Malaysian, as will be seen by the following measurements: 
Station 
number. 
Length of 
capitulum. 
Breadth of 
capitulum. 
Length of 
peduncle. 
Number 
of rings of 
scales. 
Remarks. 
mm . 
mm. 
mm. 
4942 - 
50 
32 
64 
20 
Very plump. 
4942 
44 
28.5 
55 
22 
4940 
40 
26 
35 
17 
4941 
47 
33 
58 
30 
A dry specimen in the collection of the Academy of Natural Sciences of Philadelphia has a very 
short peduncle; length of capitulum 44, width 28.5, length of peduncle, 20 mm. with 14 close scale 
rings. In dry specimens the peduncle contracts a good deal, bringing the spaced scale rings close 
together. The type originally figured by me was a dry specimen, which probably had originally a 
peduncle fully as long as any of the variety robusta. It has about 26 rings of scales. 
Scaipellum stearnsii var. gemma Hoek (= Scalpellum inerme Annandale) I regard as a distinct 
species. 
A young specimen (pi. ix, fig. 1) from station 4942 shows some suggestive features. The capitulum 
is 8.5 mm. long, 4.5 wide. The umbo of the scutum is apical, and that of the Carina is nearly so, being 
within 1 mm. of the apex, the total length of the carina being 7 mm. The inframedian latus is 
comparatively much narrower than in adult individuals, and is somewhat contracted in the middle, 
the umbo being situated below the middle near the rostral border. In shape this plate reminds one of 
that of S. idioplax and its allies. The carinal latera project very little below the carina. No rostrum 
is visible. The plates are closely juxtaposed, without the wide chitinous sutures of the adult stage. 
These several characters, especially the positions of the umbones and the shape of the inframedian 
latus, approximate to the structure of Arco scalpellum , and inasmuch as they probably represent 
an ancestral condition, they indicate that the typical group of Scalpellum is a divergent phylum, 
Arcoscalpellum being a more conservative group. The specimen figured is no. 38678 U. S. National 
Museum. 
Subgenus ARCOSCALPELLUM Hoek. 
GROUP OF SCALPEELUM VELUTINUM. 
This group was defined in Bulletin 60, U. S. National Museum, page 26, where the American species 
are described. The following species belong here, all being deep-water forms: 
Scalpellum velutinum Hoek. 
-S', regium Wyville Thomson. 
5 . regium latidorsum Pilsbry. 
5 . regina Pilsbry. 
5 . darwini Hoek. 
S. gig as Hoek. 
5 . giganteum Gravel. 
S. moluccanum Hoek. 
S. rubrum Hoek. 
5 . antarcticum Hoek. 
5 . sociabile Annandale. 
5 . alcockianum Annandale. 
S. pedunculatum Hoek. 
5 . indicum Hoek. 
S. hirsutum Hoek. 
.S', hawaiiense Pilsbry 
Scalpellum rubrum Hoek. [PI. vm, fig. 1, 2, 3, 4.] 
1883. S. rubrum Hoek, Challenger Report, Zoology, vol. vm, p. 91, pi. 4, fig. 18. 
This species was described from one specimen with the capitulum 5 mm. long, taken by the Chal- 
lenger at station 204, near Luzon, in 100-115 fathoms. This specimen is described as “beautifully red 
and white colored”, but without details as to the pattern. Its valves are “not covered by distinct 
membrane,” and nothing is said of cuticular hairs. The internal organs were not examined. 
