Meduse of the Philippines and of Torres Straits. 173 
in the radius of each tentacle and rhopalium, 16 in all. These vessels fork 
before reaching the tentacles or rhopalia, and their diverging ends curve around 
the edges of the lappets and form a marginal ring-canal. 
I believe that Periphylla hyacinthina can not be separated specifically from 
P.dodecabostrycha. The shape of the bell is quite variable, and when large 
the medusa usually becomes relatively flat and dome-like, whereas it is rela- 
tively high and conical when young. P. hyacinthina is said to be densely 
pigmented with purple-brown so that the gonads can not be seen through the 
bell walls, whereas P. dodecabostrycha is said to be less densely colored and 
semi-translucent. This distinction does not always apply and certainly the 
degree of pigmentation appears to be quite independent of the shape of the 
bell, whether flat and dome-like or high and pointed. Browne (1910), in his 
study of the Seyphomedusz of the Atlantic National Expedition, concludes 
that P. dodecabostrycha is probably only a large-growth phase of P. hyacin- 
thina, and with this opinion I am heartily in accord. 
Periphylla hyacinthina Steenstrup. 
The Albatross obtained 21 specimens of this common deep-sea medusa 
among the Philippine Islands, between depths of 338 and 1,291 fathoms, as 
follows: 
Depth Character of Size and number 
bottom. of specimens. Variety. 
Station. | Date. 
1908 Fathoms. 
D 5201 and D 5203 off | Apr. 10 | 554 to 775 | Gray sand and | 2 large 190 mms Dodecabostrycha. 
Limasaua Island. mud, and green wide, 105 high. 
mud, 
; 1909 
D 5373, near Marinduque | Mar. 2 338 Soitisandae. nyre Plage’. .ton ee Dodecabostrycha. 
Island, about 15 miles 
off shore. ; | 
D 5379, about 37 miles off | Mar. 4 OZON lessees a siete eee Ns 4 medium...... Dodecabostrycha. | 
ompog Island, near 
Marinduque Island. 
D 5471, from about 15 | Mar. 19 GE oil iredracs a aherater sors forme snaistnre ett cen orerceereees Hyacinthina. 
miles off Point Light, 
east coast of Luzon. 
D 5486, from 6 miles off | July 31 HS lho o saan aacnbasne 7 large and me- | Dodecabostrycha. | 
Batobobo Point, Pa- dium. | 
naon Island. 
D 5497, about 10 miles | Aug. 3 960 Green mud and} 1 large......... Dodecabostrycha. 
off Bantigui Island. fine sand. 
D 5507, off northern Min- | Aug. 5 425 Green mud and | 2 medium...... Dodecabostrycha. 
danao. fine sand. 
D 5628, Pariente Strait, | Nov. 30 1,291 Gray mud...... 1 medium......- Hyacinthina. 
about 7 miles from St. 
Lamo Island. 
D 5647, Buton Strait....| Dec. 16 519 Green mud..... 1 medium...... Hyacinthina. 
D 5652, Gulf of Boni.....| Dec. 17 BBE Hes arctaieuccaqegeracues tess 1 médium.. .....< Hyacinthina. 
Genus LINUCHE Eschscholtz, 1829. 
Linuche, EscHscHOLTz, 1829, Syst. der Acalephen, p. 91. 
GENERIC CHARACTERS. 
Coronate with 8 rhopalia, 4 perradial and 4 interradial. 8 tentacles, 16 
marginal lappets. With hernia-like sacs of the gastrovascular cavity pro- 
truding from the floor of the subumbrella. 8 gonads grouped in 4 pairs close 
to the 4 perradii. The central stomach opens by 4 perradial ostia into a ring- 
sinus which in turn breaks up into 16 branching, radiating pouches in the 
lappets. A marginal ring-canal is present in the Pacific L. aquila, and accord- 
ing to Vanhéffen also in L. unguiculata of the Atlantic. 
