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MEDUSAE OF THE WORLD

VOLUME III

THE SCYPHOMEDUSAE

BY

ALFRED GOLDSBOROUGH MAY0R

WASHINGTON, D. C.

PUBLISHED BY THE CARNEGIE INSTITUTION OF WASHINGTON

1910

,

CARNEGIE INSTITUTION OF WASHINGTON PUBLICATION No. 109, VOL. Ill

were first issued

AU 10

5 /

CONTENTS.

VOLUME III.

( )rdi-r Can Ink id. i-

I'IIK h.m lulls trtraptcra 506

Can Inlca marsupialis 507

rastonn 508

xaymacana 509

aurifcra 510

alata 510

( )idcr Stauromedusae

Eleutherocarpidx 519

Cleistocarpidae 519

Tessera 522

Tesserantha 522

Tesseraria 522

Depastrum cyathiforme 524

Stenoscyphus inabai 525

hexaradiatus 525

Lucernaria quadricornis . . . .527 pyramidalis 528

( )rdcr Coronata-

Periphyllidae 541-548

Pericolpa quadrigata 542

campana 542

tetralma 542

Periphylla hyacinthina 544

forma dodecabostry-

cha 546

forma regina 546

Periphyllopsis braueri 547

Nauphantopsis diomedez . . .548

Paraphyllinida? 548-550

Paraphyllina intermedia. . . .549

Order Semaeostomeae

Pelagidae 569-591

Pelagia noctiluca 570

var. ncglccta 574

ivanclla ^74

panopyra.. ..575

var. placenta 575

flaveola 576

pi-rla 576

phosphora 576

crassa 576

Chrysaora hysoscella 579

var. blossevillei 581

var. fulgida 581

blossevillei var. plocamia .581

lu-lvola 581

var. calliparea 582

var. chim-nsis 582

nulanaster 582

var. gilberti 582

Catybdea alata var. pyramis.5ii

var. grandis 511

var. iiiD.si-ri 512

nuinav ana 512

Tamoya haplonema 513

Tripedalia cystopliora 514

. . 504 518 Chiropsalmus quadrumanus.515

buiti-ndijki 515

quadrigatus 516

y,v<;i>m ma 517

Chirodropus gorilla 518

Lucernaria ^altt-ri 529

kiiki-nthali 529

hai-ckeli 529

infundibulum 529

campanulata 530

australis 530

KislnniHU i-.i naijatensis 531

I laliilystus auricula 532

octoradiatus 5^4

salpinx 535

llaliclystus sti •jncgi ri 555

antarcticus 536

Li rgudensu 536

I lalimocyathus platypus. . . .537

lagen:> 537

Craterlophus tt-thys 538

macrocystis 538

Capria sturdzii 539

l.ipkca ruspoliana 540

Ephyropsidz 550-560

Palephyra antiqua 551

pi-lagica.. ..552 indica 55,'

Nausithoe punctata 554

clausi 556

challenged 556

albatrossii 557

ni lira 557

P'«a.. 557

I.inuche unguiculata 558

Dactylometra lactea 583

quinquecirrha 585

afncana 588

fcrruginasti-r 588

longicirra 589

Kuragca depressa 589

Sandi-ria malax crisis 590

C'yaiK-iila- 591-604

Desmonema gaudichaudii. . .593

chierchiana 593

I'v.im-a capillata 596

var. fulva 600

var. vcrsicolor 600

var. no/akii 6oi

annaskala 601

Drymonema dalmatma 603

gorgo 604

Patera 604

Donacostoma 604

S4i-569

Linuche a<|uila 560

Collaspidx 561-567

Atolla bairdii 563

forma valdivi;e 565

gigantca 565

chuni 566

\\yvillt-i 566

forma vcrrillii 567

Atorcllid.i' 567-569

Atorella subglobosa 568

vanhofFeni 568

569-630

I rimaridae 604-630

Moresca paithenia 605

Discomedusa lobata 607

philippina 607

I'ndnsa undulata 609

1 )ipulmai is antarctica 610

Stln nnnia albida 6l I

Phacellophora camtscliatica.6i3

sicula 613

ambigua 615

ornata 616

Poralia rufcsccns 617

Ann Ilia aurita 623

forma marginahs. . . .627

dubia 627

solida 627

labiata 628

maldivensis 629

Aurosa furcata 630

III

IV

CONTEXTS.

Order Rhizostom.-c

Rhizostomata pinnata . .635-650

Toreuma dieuphila 636

Cassiopea andromeda 637

var. zanzibarica 639

var. malayensis 639

var. maldivensis 639

var. acyclobha 640

xamachana 641

frondosa 647

ornata 648

var. digitata 648

depressa 649

var. picta 649

mertensn 649

ndrosia 650

Rhizostomata dichotoma 650-63

Cephea octostyla 652

var. coerulescens 653

cephea 654

var. conifera 655

var. dumokuroa 656

var. coerulea 657

var. setouchiana 657

typhlodendrium 658

Cotylorhiza tuberculata 659

Polyrliiza vesiculosa 663

Rhizostomata triptera . .663-691

Catostylus mosaicus 666

Fossil Medusa?

Medusma radiata 7'5

princeps 715

deperdita 715

Paraphyllites distmctus 715

Cannostomites multicirrata. . 716

Atollites minor 716

zitteli 716

Appendix

Preoccupied Generic Names. 71 9

Corynitis = Linvillea 719

Slabberia = Dipurena 719

Turns and T lara =Clavula. .719

Laodicea 7'9

Hydromedusse 720-726

Pennaria tiarella 720

Corymorpha nutans 720

Sarsia rosaria 720

japonica. . . 720

Eleuthena 721

Cladonema radiatum 721

Catostylus cruciatus. . . .

palmipes

tagi stuhlmanni. .

stiphropterus. viridescens. . . ornatellus. .

tnpterus

purpurus

Lychnorhiza lucerna

bartschi

Crambione mastigophora .

cookii

Mastigias papua

var. siderea

var. sibogz

ocellata

pantherina

gracile

rosea

Pseudorhiza aurosa

haeckelii

Phyllorhiza punctata

Yersura palmata

vesicata . .

pinnata .

631-714

.667 Versura anadyomene 686

. 667 maasi 687

. 668 Labonema smithii 689

.669 Rhizostomata lorifera. . .691—697

.669 Thysanostoma thysanura . . .692

. 670 Lorifera lorifera 694

. 670 var. pacitica 695

. 670 flagellata 695

. 671 Leptobrachia leptopus 696

.671 Rhizostomata scapulata. 697-71 1

.673 Rhizostoma pulmo 699

. 674 var. lutea 703

. 676 var. octopus 703

. 677 var. corna 703

. 678 var. capensis 703

. 679 Rhopilema esculenta 704

. 680 hispidum 706

. 680 verrillii 707

. 681 Eupilema scapulare 709

.681 Stomoloplius meleagris 710

.681 var. fritillaria 711

.682 Rhizostomata simplicia. 712-714

.683 Archirhiza aurosa 712

. 684 Haplorhiza simplex 713

.685 punctata 713

.686 Cannorhiza connexa .-/H

.686 Stomatonema reticulatum. . .714

Acraspedites antiquus . . . Semaeostomites zitteli . . Eulithota fasciculata . . . . Myogramma speciosum.

Medusma costata

geryomdes

...715-718

.716 Laotira cambria 717

.716 Dactyloidites asteroides 717

.716 Rhizostomites admirandus . .718

. 716 Brooksella alternata 718

.717 confusa 718

.717 rhenana 718

Urashimea globosa

Turntopsis pacifica

Rathkea octopunctata . .

var. grata

Xemopsis dofleini

V\ illsia pacifica

Pnlvorchis karafutoensis .

Spiroccdon saltatrix

Obelia congdom

Stauropliora mertensir. . .

Cubaia gemmifera

Craspedacusta sowerbii. .

.722 .722 .722 .722

723 •723 -723 •724

724 •724 •725 •725

Microhydra n lieri ......... 726

Limnocnida ............... 726

i£gina citrea .............. 726

Scyphomedusae ....... 726—728

Can bdea rastomi .......... 726

alata .................. 726

Haliclystus octoradiatus . . . .726

Thaumatoscyphus dis-

tinctus ........... 727

Parumbrosa polvlobata Ephyropsites jurassicus

728 728

MEDUSAE OF THE WORLD.

THE SCYPHOMEDUSAE.

INTRODUCTION.

The present volume is a continuation of the work the two former parts of which dealt with the Hydromedusae. The acknowledgments which I was privileged to render in the introduction to the first volume need not here be repeated, pleasurahle to me as such a repeti- tion would be. Suffice it to say that the work was commenced in 1892 at the suggestion of Dr. Alexander Agassiz whose generous aid enabled me to pursue these studies for man)- years under the most advantageous conditions; and apart from the sense of personal gratitude I cherish toward Dr. Agassiz I hope that enough of scientific worth may be found within these volumes to cause it to appear that I have made appreciative use of the opportunities he so magnanimously accorded to me. Throughout the years I have hoped that Dr. Agassiz might live to see this work and that he might be pleased by this fruit of his inspiration, but on March 27, 1910, the great student of the oceans died upon the sea, only a few weeks before the publication of these volumes.

Since the first two volumes passed under the press I have been most kindly aided by the United States Bureau of Fisheries and by the National Museum of the United States, at Washington. The authorities of the former permitted me to study the important collection of Scyphomedusae recently made by the Albatross in the Philippine Islands, and those of the latter institution were so courteous and helpful as to set aside for my use a table in the Smithsonian building in order that I might study this collection to the best advantage. It is due especially to Dr. Hugh M. Smith, Deputy Commissioner of the Bureau of Fisheries, and to Dr. Richard Rathbun, Assistant Secretary of the Smithsonian Institution that I owe these highly appreciated favors.

Plates 61 and 64A and several text-figures are taken from drawings made from nature by my friend, the late Prof. William K. Brooks. These drawings were most kindly presented to me for publication in this work by Prof. E. A. Andrews, of the Johns Hopkins University, soon after the death of Professor Brooks. They will serve as memorials of the rare skill in observation and in draftsmanship of the great naturalist who made them.

SCYPHOMEDUS/E.

Phanerocarpf, ESCHSCHOLTZ, 1829, Syst. der Acal.

Sttganofithalmit, FORBES, 1848, British Naked-eyed Medusa:.

Acraipedif, GECENBAUR, 1856, Zcit. fur wisscn. Zool., BJ. 8.

Dncoplior*, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4.

Acraspedx, HAECKEL, 1880, Systems dcr Mcdusen, Halfte 2.

Scyphomcdusx, LANKESTER, 1881, Encyclopedia Britannica, Ed. 9, Hydrozoa, p. 547.

Medusiform Cnidaria with tentacle-like, entodermal filaments upon the subumbrella floor of the stomach-cavity. With entodermal gonads, and without a velum such as is characteristic of the Hydromedusae. Development by strobilization from scyphostoma larva?.

There is but little cvidi-nce to support the supposition that the Scyphomedusae have been derived from the Hydromedusae. The medusa shape of the sexual generation in both has in all probability been acquired independently. Indeed, various animals have assumed the external appearance and peculiar mode of locomotion by pulsation which is characteristic of the medusae. Such for example are the protozoan Craspedotella and the holothurian Pfla-. gothuria. Moreover there is reason to believe that the medusa-bell of the Narcomedusae has

499

500 MEDUSA OF THE WORLD.

been acquired independently of and is not homologous with the bell of the Leptolina medusae. (See Goette, 1907, Zeit. fur wissen. Zool., Bd. 87, p. 289.)

The peculiar velum of the Carybdeidae among the Scyphomedusae is a structure of the subumbrella, not of both subumbrella and exumbrella as in Hydromedusae. It may be regarded as a parallelism, and not genetically related to the velum of Hydromedusae. The exumbrella nerve-ring, found commonly in Hydromedusae, does not exist in the Scyphomedusae, but is replaced by a subumbrella plexus of fibers extending between the marginal sense-organs and also radially inward from these ganghomc centers. There is also a diffuse, nervous, epithelial, ectodermal network over the subumbrella. The subumbrella alone is sensitive to stimuli, the exumbrella being non-sensory, but covered with a nematocyst-bearing epithelium.

In the Scyphomedusae the mature, sexual products are found in the entoderm, whereas they are usually in the ectoderm in Hydromedusae. The velum which is universally present in Hydromedusae is absent in Scyphomedusae. The 4 interradial, gastric septa which are always seen in the scyphostoma larva of Scyphomedusae are not found in the polyp stage of Hydromedusae.

When we come to consider the relationships of the several orders constituting the Scypho- medusae themselves we meet with difficulties which render our classification only tentative. The history of the attempts to classify the Scyphomedusae have recently been reviewed by Maas, 1907 (Ergeb. und Fortschritte derZool., Bd. I, p. 189), and by Bigelow, 1909 (Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 13). Marked advances over Haeckel's artificial classification were made by Claus, 1878, 1883, who showed that the Carybdeidae are a very aberrant group not closely related to other Scyphomedusae, and not descended from the Stauro- medusae as Haeckel believed. As Claus showed, the interradial, gastric septa in Carybdeidae may be newly arisen fusions of the entodermal walls of the exumbrella and subumbrella and not derived from the interradial taeniolae of the scyphostoma. Unfortunately, however, no one has seen the late scyphostoma stage in Carybdeidae, and hence our knowledge of their rela- tionships must remain doubtful. Claus, 1883, and VanhofFen, 1892, called attention to the supposed importance of the presence or absence of the interradial, gastric septa in the classi- fication of sexually mature Scyphomedusae but we must remember that these are absent in Semaeostomae and found in Coronatae, yet these two orders are closely related. Moreover, interradial gastric septa are found both in Stauromedusae and Carybdeidae yet all modern students agree that these groups are widely divergent. The sessile Stauromedusae certainly approach very closely in structure to the type of the scyphostoma, but this may be the result of degeneracy due to their sedentary habit.

VanhofFen, 1892, in a masterly paper called attention to the importance of the annular furrow and marginal, exumbrella sculpturing of the bell in certain of Haeckel's Discome- dusae, and he grouped these under the designation Coronatae. Claus, 1883, had previously shown that in Naiisitlwe, which is a typical member of the Coronatae, the interradial septa of the central stomach are derived from the 4 taemolae of the scyphostoma. These septa are, how- ever, absent in the medusa-stage in Semaeostomeae and Rhizostomae, although they are found in the scyphostoma.

All evidence both anatomical and embryological shows that the Rhizostomae are descended directly from the more simply organized Semaeostomeae. It is probable that the Coronatae and Semaeostomeae are not descended one from the other, but are derived from some common ancestral stock which has disappeared. The Stauromedusae may represent a highly specialized derivative from this common ancestral form, their specialization being due to their sessile, attached habit of life. The Carybdeidae are so aberrant and our knowledge of their develop- ment is so imperfect that we have not yet been able to determine their relationships to other Scyphomedusae.

The habits and distribution of the several orders of Scyphomedusae are characteristic. The Stauromedusae are found only in the Arctic and Antarctic regions and in cold seas, and are unknown from the tropics; thus furnishing us with an interesting problem in dis- tribution. The planula is not pelagic but creeping and is devoid of cilia, and the medusae are sessile or creeping, and do not pulsate rhythmically. They affix themselves to seaweeds and rocks and rarely move from their places of attachment. They are probably degenerate forms although their relationship to other Scyphomedusae is uncertain. They are confined to the shores, but may be carried far from their normal habitats upon drifting seaweed.

SCYPHOMEDUS^E.

501

The Orders of the Scyphomcdusce.

	Carybdeid.T.	Stauromedusa?.	Coronatar.	Scma?oston.	Rhizostomx.
Form of bell.	Cubical with inter-	Pyramidal, usually	Discoidal with an-	Discoidal without	As in Semxostomca;.
	radial angles, and	attached to objects	nular furrow, and	annular furrow or
	perradial sides.	by aboral apex.	marginal zone of	pedalia.
			pcdalia in cxum-
			brella.
Margin of bell.	No lappets but with	Usually with 8 ad-	Cleft into lappets.	Cleft into lappets.	Cleft into lappets.
	an annular mem-	radial lobes which
	brane formed from	bear the tentacles.
	the subumbrella
	and constituting a
	velum.
Tentacles.	4 interradial, single	Usually 8 adradial	Arising from clefts	Ariiing from sub-	if. In one
	or in clusters. Ten-	clusters of hollow,	between lappets.	umbrella or from	genus (Lobonema)
	tacles hollow, lash-	knobbed tentacles.		clefts between	the marginal lap-
	like, and mounted			lappets.	pets have been
	upon spatula-shaped				metamorphosed
	projections of the				into tentacle-like
	subumbrella.				organs.
Sense-organs.	4 perradial clubs set	When present 8 (4	Arising from clefts	As in Coronata?.	As in Coronat.e.
	in niches on sides	perradial, 4 inter-	<-n lappets.
	of bell. Ocelli and	radial) anchors	An entodcrmal
	lithocyst present.	without ocelli or	mass of concretions
		lithocysts.	always present.
Interradial septa	Present.	Present.	Present.	Absent.	Absent.
in stomach.
Mouth .	Cruciform, simple.	Cruciform, simple.	Cruciform, simple.	I'nit.iry. Cruci-	Numerous mouths
				form, usually with	surrounded by mo-
				veil-like lips.	tile tentacles and
					borne on 8 ad-
					radial, fleshy, arm-
					like processes.

The Carvbdeidas are highly specialized forms which are confined to tropical and warm seas. They live upon the bottom in shallow water along coasts, and are not commonly Inuiul upon the surface until nearly mature. Their developmental stages are practically unknown and their exact relationship to the other orders of Scyphomedusz is problematical. In com- mon with the Stauromedusae and Coronatx thtv have 4 perradial stomach-pouches. They bear a remarkable, but wholly superficial, resemblance to the Hydromedusae in the shape o| tin- bell and in the presence of an annular diaphragm which constricts the aperture of the bell-cavity. This velar diaphragm is, ho\ve\er, only an extended part of the subumbrella in Carybdeid;c whereas both exumbrella and subumbrella take part in its formation in I Ivdromedusae.

The Coronatae are deep-sea and pelagic forms and are therefore of world-wide distri- bution in common with other creatures of similar habits.

The Semaeostomeae are mainly coastal forms which develop through stabilization fiom scyphostoma larvae. The genus Pelngia is peculiar, however, in that the larva is not attached, but remains free-swimming and develops directlv into the medusa; and thus it is that medusa? of this genus are widely distributed, independently of the proximity of land and are found in all warm seas. Certain families, such as the Cyaneidae, are practically confined to the Arctic and Antarctic, and to cold scas;whereas the Pelagidae are found only in warm oceans. On the other hand the genus AurcUia is of world-wide distribution.

The Rhizostomas form a well-defined order which are clearlv descended from the Scmre- ostomeas. They are confined to tropical and warm seas and are most abundant in the M.tl.n Archipelago. They develop through strobili/.ation from scyphostoma larva1, and are theic Ime confined to coastal waters of a depth suitable for the maturation of their attached larx.e.

In the Semxostomeae and Rhizosromae the egg .!< M lops into ;i p\ riforni. ciliated planula which is set free from the mouth-folds of its parent and swims freely through the water. Soon it attaches itself by means of its forward end. An ectodermal imagination is said by Goette to

502 MEDUSA OF THE WORLD.

occur at the non-attached, upper pole of the larva. 4 perradial stomach-pouches develop, 2 being partially ectodermal and derived in some measure at least from the invaginated ectoderm of the oesophagus, the other 2 pouches being entodermal and derived from the entoderm of the stomach of the larva. These perradial pouches are separated by 4 interradial septa which finally become perforated near the margin forming a peripheral ring-sinus. 4 funnel-like cavities lined by longitudinal muscle-fibers sink downward into these 4 interradial septa from the hypostome of the larva, and tentacles develop around the margin of the hypostome. Finally the larva splits by transverse clefts into a series of discoidal, free-swimming, ephyra larvae, and the original corona of tentacles is cast off and dies while a new set of tentacles and a 4- cornered mouth may develop at the upper end of the remaining part of the larva. In some species, and under certain conditions, this strobilization may be monodiscus and give rise to but a single ephyra, while in others from 10 to 30 ephyrae may arise from a single scyphostoma. Details of this peculiar process of delamination and regeneration, and of the larval stages in general, will be found in Korschelt and Heider's text-book of the embryology of invertebrates, part I, 1895, pages io'2 to 122, and throughout the text of the present work. See especially Cyanea arctica, Auretlia aurita, Pelagia, Chrysaora, Cotylorhiza lubcrculata, and Cassiopea xamachana.

With reference to the relationships between Hydromedusae, Scyphomedusae, and actinians, Goette's announcement that the oesophagus of the scyphostoma of Scyphomedusae is formed of invaginated ectoderm seemed to suggest a close relationship between the scyphopolyp and the actinozoa. Hadzi, 1907, however, re-affirms the work of Claus and supports the view that the oesophagus of the scyphostoma is lined on the inside with entoderm and is not invaginated but evaginated from the primary stomach. All of the stomach-pouches are therefore ento- dermal according to Clans and Hadzi, whereas, 2 of the primary stomach-pouches are at least partially ectodermal and 2 wholly entodermal according to Goette.

We know, however, from Conklin's study of the development of Linuche, and Hyde's research upon Aurellia, that gastrulation in one and the same species may occur either through invagination or by ingression, and judging from the mass of evidence which has been accumu- lated we can not doubt but that the mouth of the scyphostoma of one and the same species may be formed either by invagination, or by a simple breaking through of both entoderm and ectoderm in which the entoderm takes the more active part, or even by an evagination of entoderm. The three processes may thus be closely related and the manner of operation dependent upon which layer takes the initiative and assumes the more active part. It is there- fore misleading to attach any deep morphological significance or to draw any sweeping con- clusions in respect to the phylogeny of the Scyphomedusae from this process. Indeed, long ago our faith in the rigid application of the germ-layer theory has become so shaken that the discussion between the Goette and the Claus schools has lost most of its significance.

According to the Claus-Hadzi view the Scyphomedusae are more closely related to the Hydromedusae than they are to the actinians. Certainly the histological characters of the germ layers of the scyphostoma resemble the hydropolyps rather than the actinozoa, although both are so closely similar that no great weight can be attached to this fact. Herouard, 1909 (Comptes Rendus, Paris, tome 148, page 1225), supports the opposite view from histological evidence, for he finds that the cellular investment of the pharynx of Scyphomedusse and scypho- stoma larvae is similar in character to that of the gullet of Anthozoa, thus indicating a genetic relationship between the Anthozoa and Scyphomedusae.

According to Goette the 4 primary stomach-pouches are actively evaginated from the cen- tral stomach-cavity and are of mixed ectodermal and entodermal origin. According to Claus- Hadzi, however, they are wholly entodermal, and are only passively separated one from another by the infolding of the 4 entodermal foldings in the stomach-wall which constitute the tseniolae.

It is extraordinary that this contention should have persisted so long without a final settle- ment of views.

The table on the opposite page will serve to present the question more clearly.

The scyphostoma larva of Nausithoe bears a remarkable superficial resemblance to hydroids, being elongate, branched, and incased by a horny perisarc. It infests sponges.

In the majority of the Scyphomedusae the sexes are separate, but in Chrysaora and in certain Rhizostomae the medusae are hermaphroditic.

503

	Hydropolyp (hydroids).	Scyphopolyp (Scypho- stoma), according to Claus-Hadzi.	Scyphopolyp (Scypho- stoma), according to Goette.	Anthopolyp (Actinozoa).
Inner lining of oesopha- gus.	! mated and ento- derrnal.	Evaginated and ento- rjermal.	InvaginatcJ and ccto- dcrmal.	Invaginatcd and ccto- dermal.
TanioUe.	None.	4 wholly of entodcrmal i>ni;in, but with < dermal muscle-strands.	4 of mixed rctinirrut.il and entoderma] origin, but with rctodrrmal	i composed mainlv drriii
			muscle-strands.
MM- de-strands.	Formed from basal elon- gations of both ecto- derm and entmlenu cells.	Of cctodcrmal origin.	Of ectodermal origin.	Mainlv ennnlrrmal hut some eclodrrmal in origin.
Stomach-ca1. i	I'nitary, hut "ftm with irregular, longitudinal ridi;< ' lei inal 0 Us. (See Hamann, 1882, Jrna.Zeilsch. Naturw.,Bd. 15^-509.]	With 4 primary pouches of purely entodermal origin simp! ep one from another by 4 entodennal infoldings.	2 of the primary i are partially n i mal and 2 of purely entiuK-rnul origin. ' 1 /row actively outward fr»>jn sides of central stomach.	With lateral pouches.
Ripe sexual products.	In ectoderm.	In entoderm.	In entoderm.	: i'Tin.
Intermediate lamella.	Structureless, free from cells.	Containing cells.	Containing cells.	1
Mi'iK; of reproduction.	Medusa? develop In budding.	Mr.i'i r develop by stabilization.	1 'li-vrlop by strobilization.	V> ru< >i>. .r -I '-.loped.

Romanes and Eimer found that it" the marginal sense-clubs of Scyphomedusz he removed a more or less complete paralysis results, although the disk remains capable of responding temporarily to any stimulus. Bethe, 1903, found that in Rhizostoma pidino and Cotylorhiza tuberculata the pulsation-stimulus is nervous in nature, and there are many analogies between the rhythmic movement ot these medusae and that ot the vertebrate heart. For example the "all or none" principle applies to medusa?, as does also the phenomenon ot the insensibility of the medusa ro stimulation while in systole, and the extra M stole and compensating period of rest. Mayer, working upon Cassiopia xamachana, finds that the sea-water is a balanced fluid, the stimulating tendency of its sodium being exactly counterbalanced by the inhibiting effects of its magnesium, calcium, and potassium. The pulsation stimulus arises in the mar- ginal sense-clubs and is due to the constant formation of sodium oxalate in the entodennal cells at the distal end ot each club. This precipitates the calcium chlorides and sulphates of the sea-water forming the insoluble calcic oxalate crystals of the sense-club, and setting free sodium chloride and sulphate the cations ot which are powerful nervous stimulants, and produce the periodic response ot the nervous elements which causes the rhythmic pulsation.

In the hydromedusac on the other hand the function of the control ot pulsation is not localized in the sense-organs for any part of the bell-rim will serve to mainiain the bell in pulsation.

It is interesting to note that whatever the effect of the several cations, sodium, magnesium, calcium, and potassium, may be upon the neuromuscular system, their effects upon the move- ment ot cilia is the exact opposite. \\ hatever stimulates muscles inhibits cilia, and

The gastric tentacles, which arise from the subumbrella wall of the stomach on the sides of the interradial septa are very characteristic and constant structures in Scvphomcdus;e. They are entodermal with solid cores of mesogloea, and are in no sense comparable \\ith the marginal tentacles, but their function is unknown.

The marginal tentacles themselves are to be regarded as structures ot" the subumbrella. They are usually but not invariably hollow and consist of an axial core of entodermal tells encased outwardly by ectoderm which is richlv besprinkled with nematocysts. The mammal sense-clubs are highly specialized tentacles which have been transformed into sensory centers. Ocelli may or mav nor be present and when found they may be ol ectodermal or ot entodermal structure; but concretions ot crystalline nature are invariably (omul in the entodermal cells at the distal end of the club in all forms exhibiting rhythmical pulsation. The gonads are follicular foldings of the entodermal subumbrella floor of the stomach.

504 MEDUSA OF THE WORLD.

Order CARYBDEHLE Gegenbaur, 1856.

Carybdeidte, GEGENBAUR, 1856, Zeit. fur wissen. Zool., Bd. 8, p. 214.

Charybdea, CLAUS, 1886, Arbeit. Zool. Inst. Univ. Wicn, Bd. 7, p. 110. — VANHOFFEN, 1892, Ergeb. der Plankton Expedition,

Bd. 2, K. d., p. 21.

Marsupialidte, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 174. Cubomedusce, HAECKEL, 1880, Syst. der Medusen, p. 423. — GOETTE, 1887, Abhandl. zur Entwickelungsgesch. der Thiere, p. 66,

Leipzig. — SCHWEIKOFF, 1889, Morphol. Jahrb., Bd. 15, p. 25. — CONANT, 1898, Mem. Johns Hopkins Univ. Biol. Lab.,

vol. 4, No. i, p. 3. — HAACKE, 1887, Jenaische Zeitschriit, Bd. 20, p. 590. — MAAS, 1907, Ergeb. und Fortschritte der Zool.,

Bd. i, p. 197.

CHARACTERS OF THE ORDER.

Scyphomedusae with 4 perradial, knob-shaped, marginal sense-organs which are situated within niches upon the sides of the bell. Each sense-organ contains an entodennal concretion, and one or more ectodermal ocelli. There are 4 interradial tentacles or groups of tentacles. 4 wide perradial sacs extend outward from the central stomach into the interstitial space of the bell. These sacs are incompletely separated one from another by 4 narrow interradial septa. There are 8 gonads each one of which is leaf-shaped and attached along one side to an inter- radial septum, from which it extends outward into the gastrovascular space of the bell. The bell-margin is not cleft into lappets. The subumbrella forms an annular diaphragm called the velarium which partially closes the opening of the bell-cavity.

The perradial sense-organs in the Carybdeidae are knob-shaped, and are set within niches upon the sides of the bell. The stalk of each knob is hollow and connected with the gastrovascular system of the bell. The knobbed end of each club contains a large entodermal concretion and one or more ectodermal eyes (plate 56, fig. 6"). These eyes are placed on the inner or centripetal side of the club and look inward into the bell-cavity. The larger eyes are provided with a doubly convex lens, back of which is a cup-shaped space occupied by the lens-capsule and the retina. The retina is made up of a single layer of cells forming a hollow cup, into which the lens with its capsule fits. The central space of the retinal cup is clear and glassy. This transparent region is enveloped by a deeply pigmented part and back of this lies a muscular zone. The retina is made up of three kinds of cells, some long and prism-shaped, others short and pyramidal, and still others long and pyramidal. The deep-lying ends of these cells are more or less pigmented, while their outer parts are trans- parent, and being packed closely together, they form the vitreous center of the retinal cup. (See Conant, 1898; Berger, 1900; etc.)

The tentacles of the Carybdeidae are interradial and arise at a level slightly above the apparent bell-margin, although they are actually structures of the subumbrella. Their proxi- mal parts are developed into tough, gelatinous, wing-shaped or spatula-shaped structures (pedalia), which probably serve as keels to steer the animal m its course through the water. The long, distal ends of the tentacles are cylindrical and highly contractile, and their outer surface is covered with rings of nematocysts. The tentacles are hollow and their lumen is connected with the gastrovascular space of the bell. This is accomplished by the interradial septa being incomplete near the bases of the tentacles and thus the lumen of each tentacle is placed in direct connection with the gastrovascular spaces of the two adjacent perradial pouches. The flexible parts of the tentacles are armed with nematocysts, the stinging power of which is so great that the name "Sea Wasp" is commonly given to these medusae.

The velarium is an annular membrane which extends inward from the bell-margin, forming a diaphragm which partially closes the cavity of the subumbrella; superficially it bears a close resemblance to the velum of the Hydromedusae, but is separated from the exum- brella by means of a continuous sheet of entodermal tissue which penetrates the gelatinous substance of the bell all around the bell-margin, and connects the entoderm of the intermediate lamella with the ectoderm of the outer surface of the bell. It thus forms a ring of entoderm around the bell-margin which completely separates the ectoderm of the subumbrella side of the velarium from that of the exumbrella. At points other than those occupied by sense- organs or tentacles this vascular, entodermal lamella forms a simple, flat sheet, but when it comes to the tentacle-bases, or sense-organs, it makes a loop upward over them. Thus the tentacles and sense-clubs are structures of the subumbrella only, for they lie below the ento- dermal lamella which isolates them completely from the exumbrella. What the philogenetic significance of this lamella may be we do not know, and until this is discovered we can not be certain that the velarium of the Carybdeidae is not strictly homologous with the velum of the

PLATE 56.

Fig. I. Side view of Haliclystus salptnx, from eelgrass near Ram Island, off

Manchester, Massachusetts, September 7, 1905. Fig. 2. Oral view of medusa shown in figure I. Fig. 3. Section of stalk of medusa shown in figure I. Fig. 4. Side view of marginal organs of medusa shown in figure i. Fig. 5. Young medusa of Carybdea xaymacana, showing prominent nema-

tocyst-warts over the exumbrella. Tortugas, Florida, May 24,

1899. Fig. 6. Quarter-grown medusa of CarybJea xaymacana. Nassau Harbor,

Bahamas, March, 1893.

Fig. 6'. Side view of one of the sense-clubs of medusa shown in figure 6. Fig. 6". Section of sense-club of medusa shown in figure 6. /, ectodermal

lens of cup-like eye; oc, ocellus; ot, otolith. Entoderm brown,

ectoderm gray. Fig. 7. Carybdea xaymacana showing gonads; twice natural size. Nassau

Harbor, Bahamas, April 24, 1907.

Fig. 7'. Side view of the sense-club of the medusa shown in figure 7. Fig. 7". View of the sense-club of the medusa shown in figure 7, showing side

that faces inward in such manner as to observe objects within the

bell-cavity.

Drawn from life, by the author.

MAYEM

'

•

6'

*

CARYBDEID.E. 505

Hydromedusae; for it constitutes the only important point of difference in the velar diaphragms of the two sorts of animals. The velarium is commonly bound to the wall of the subumbrella by 4 solid, bracket-like supports, the frenulae, one of which is found in each pi-rradius. There is also a more or less complicated system of entodermal canals or pouches which extend into the substance of the velarium from the gastrovascular space of the bell.

There has been a tendency among modern authors to regard the velarium as being com- posed of a series of fused lappets, the pouches being remnants of lappet-pouches. \Ve have no proof, however, that this is the case, and the velarium in the youngest Charybdeidx \ et seen is as entire as in the adult.

There are 4 groups of gastric cirri, or phacelli, in the interradial corners of the central stomach, at the inner ends of the 4 interradial septa, and this feature alone would distinguish these forms from the Hydromedusae in which no such structures have been observed. The gonads, also, are entodermal instead of ectodermal when mature as in Hydromedusae. Both the gonads and gastric cirri are structures of the subumbrella, as is also the entire muscular system.

There is a well-developed nerve-ring on the bell-cavity side of the subumbrella near the margin. This ring forms 4 loops upward to the 4 perradial sense-organs (plate 57, fig. 2). There are 8 ganglia upon the nerve-ring, 4 perradial and 4 interradial. Each of the perradial ganglia sends off 2 nerve-roots, which pass through the gelatinous substance of the subumbrella and fuse as they extend down the inner (centripetal) side of the stalk of the sensory-club. I he 4 interradial ganglia are situated at the bases of the tentacles into which they probably send nerve-fibers.

The Carybdeidae are inhabitants of" the warmer waters of all the oceans, and none of them has been found in the Polar seas. Most of them have been taken in the open ocean, but they are also found swarming in harbors and other places near land. When young they appear to be bottom forms, but they usually come to the surface when mature.

But little is known concerning the embryonic development of these forms. Conant, 1897, found that in TripeJalia the ovum develops into a free-swimming planula, which soon settles down upon the bottom and becomes a hydra-like polyp with a mouth and 4 tentacles. Haacke, 1887, found a very young individual of (,ur\lidcii rastotni in which a short style canal extendi d upward from the upper floor of the central stomach to the aboral apex of the bell, and he believes it possible that this structure may represent the remnant of some connection between the young medusa and some form of scyphopolyp nurse, but this is wholly problematical.

Haeckel, 1880, believed that the Carybdeidae were descended from the Stauromedusae, as, according to him, were also his Periphyllidae and the Discomedusas. He Ix IKMS that morphologically the Carybdeidae are intermediate between the Periphyllida? ami the Disco- medusae. All of this, however, is speculation unsupported by a single fact of am significance. We must first learn more of the early embryonic stages ol the medus;i- <>t the Carybdeidae and Stauromedusx before we venture to state how they may be related in philogeny to other Scyphomedusae. They have perradial stomach-pouches which are partially separated by interradial septa as in the Stauromedusx; indeed Goette, iSS^. \\ould consider the Canli- deidae as an off-shoot of or cousins of the Stauromedusx.

Most of our knowledge of the anatomy of the Carybdeidae is due to the labors of Clans. 1878; Haeckel, 1880; Schewiakoff, 1889; Conant, 1898; and Berger, 1900.

Berger, 1900, reports upon a few physiological experiments upon the reactions of Caryb- deidae (see C. xaymacana). A synopsis of the genera of the Carybdeidx follows:

( ?) Procharybdis Haeckel, 1880. 4 simple pcdalia. Velarium without velar canals or frcnuke. This is probably only

a young Charybdea. Carybdea Pcron and Lesucur, 1809. 4 simple pedalia. Velarium with velar canals and with 4 pcrradial bracket-like

supports (frcnuta). Stomach small, without hollow bracket-like sides arching over between it and the subumbrella.

Stomach small and simple, with 4 horizontal clusters of gastric cirri. Tamova F. Mulltr, 1859. Similar to Charybdea, but with a large stomach which is bound to the subumbrclU by 4

pcrradial, hollow arches and with 4 vertical, interradial clusters of gastric cirri. Triptdalia Conant, 1897. Numerous, 8 to 12 or more, simple unbranchcd pedalia arranged in 4 interradial clusters.

No hernia-like subumbrvlla sacs. Chiropsalmus L. Agassi:, 1861. 4 branched, hand-shaped pedalia with tentacles arising from the tips of the fingers.

With 8 simple, finger-shaped, hernia-like subumbrella gastric sacs. Free-margins of the 8 gonads entire and simple. Chirodrapus Haeckel, 1880. Pedalia hand-shaped as in Chiropsalmus. 8 branched, hernia-like sacs projecting into

the subumbrella from the 4 perradial stomach-pouches. Free-margins of the gonads showing grape-like swellings.

506 MEDUSA OF THE WORLD.

Genus (?) PROCHARYBDIS Haeckel, 1880.

Procharybdis, HAECKEL, 1880, Syst. der Medusen, p. 437.

The type species is P. tetraptera Haeckel from the Sunda Islands, Indian Ocean. It may prove to be only a species of Carybdea which is regenerating its velum or is immature.

GENERIC CHARACTERS.

Carybdeidae with 4 simple, interradial tentacles with pedalia. Velarium simple, without velar canals or frenulse.

P. turncula and P. flagellata of Haeckel, loc cit., p. 438, are both too inadequately known to be profitably retained in scientific literature. P. cuboides Haeckel, is, I believe, a young stage of the common Carybdea rastonn. The briefly described Procharybdis securlgera Haeckel, loc cit., p. 640, from the Pacific coast of Central America, may be C. rastonii, but it is said to have tentacles which terminate each in a knob. This character is seen in young individuals of Carybdea.

Procharybdis tetraptera Haeckel.

Procharybdis tetra/itera, HAECKEL, 1880, Syst. dcr Medusen, p. 437, taf. 25, 6gn. 3, 4.

Bell dome-like with thick walls, 30 mm. high, 20 mm. wide. 4 very large, flat, expanded, simitar-shaped pedalia, with blunt outer ends; these pedalia are nearly as long as the bell- height and nearly one-third as wide as they are long; they are relatively larger than in any other known form of Carybdeidae. The 4 perradial sense-clubs are set in niches nearly as far above the bell-margin as the width of the bases of the pedalia. Each sense-club is small and apparently contains only a single very large eye and an entodermal concretion. Each of the flexible, hollow tentacles tapers to a pointed end. They are ringed with nematocysts and are about 1.5 times as long as bell-height.

The velarium is without velar canals or bracket-like frenulas, and its margin is entire. It is only about twice as wide as the tentacles and appears to be very rudimentary. It occurs to me that this velarium may be regenerating after having been lost through accident. Should the velarium have velar canals and frenulae, the medusa would be one of the genus Carybdea which it resembles in all other respects.

The stomach is small, wide, flat, with 4 large, pointed lips. There are 4 pairs of gastric cirri in the interradial corners of the stomach, each consisting of an axial shaft which gives rise to 20 to 30 filaments on one side. The 8 gonads are developed as in other species of Carybdeidae on both sides of the 4 interradial septa.

Haeckel describes this medusa from a single preserved specimen found in the Sunda Archipelago, Indian Ocean.

Genus CARYBDEA Pe"ron and Lesueur, 1809.

Carybdea, PERON ET LESUEUR, 1809, Tableau des Meduses, Ann. Mus. Hist. Nat., tome 14, p. 331. — MILNE-EDWARDS, 1833,

Annal. des Sci. Nat., tome 28, p. 248 Charybdea, CLAUS, 1878, Arbeit. Zool. Inst. Univ. Wien., Bd. I, p. 221. — HAECKEL, 1880, Syst. der Medusen, p. 439; 1881,

Deep-sea Medusae Challenger Expedition, Zool., vol. 4, p. 91. — CONANT, 1898, Mem. Biol. Lab. Johns Hopkins Univ.,

vol. 4, No. i, p. 3. — HAACKE, 1887, Jenaische Zeit. fiir Naturwissen., Bd. 20, p. 590. — BIGELOW, H. B., 1909, Mem. Mus.

Comp. Zool. at Harvard College, vol. 37, p. 17. — MAAS, 1909, Abhandl. Aadk. Wissen., Miinchen, Suppl. Bd. i, Ahandl.

8, p. 40.

The type species is C. marsupialis Peron and Lesueur, of the Mediterranean.

GENERIC CHARACTERS.

Carybdeidae with 4 simple, interradial pedalia and tentacles. Velarium supported by 4 perradial, bracket-like frenulse which bind it to the subumbrella. Velar canals present. Stom- ach small, without bracket-like mesenteries joining it to the subumbrella. Development unknown.

Peron and Lesueur spell this generic name Carybdea; Agassiz, 1862, Cont. Nat. Hist. U. S., vol. 4, p. 173, changed it to Charybdea.

All the species of this genus are inhabitants of warm seas. None have been taken north of Cape Cod on the North American coast, or north of the Mediterranean in Europe. Owing to the slight differences between them, it is exceedingly difficult to separate the species one

CARYBDEID.E — CARYBDEA. 507

from another. The most characteristic features for specific distinction are the shape and size of the pedalia and the number and character (branched or unbranched) of the velar canals.

Carybdea marsupialis, C. rastonii, and C. xaymacana are very closely related, if not mere varieties, of one and the same medusa. They are found in the Mediterranean, tropical Atlantic, and Pacific.

C. pyramis, which appears to be identical with Haeckel's C. obeliscus and C. alata is distinguished by its long, simitar-shaped pedalia. It comes from the tropical Atlantic.

C. grandis and C. moscri are closely related tropical Pacific forms and may be mere local varieties, one of the other, indeed Bigelow, 1909, believes them to be mere growth stages of one and the same medusa, C. moseri being the younger. C. grandis is possibly identical with Bursarius cytherece Lesson ( = Tamoya bursaria Haeckel) but the descriptions of the last- named medusa are so vague that it must, I think, be dropped from our lists.

C. murrayana Haeckel is distinguished by its large number of profusely branched velar canals. In other respects it closely resembles C. marsupialis, of which form it may indeed be a mere variety.

Semper's Philippine Island Carybdea, called C. philippina by Haeckel, may be identi- cal with C. moseri, but is too vaguely mentioned to be recognizable.

C. verrucosa Hargitt, 1903, is a very young form, too immature for identification.

C. aurifera Mayer is distinguished by its rosin-colored bell, being far darker in color than in any other species.

Haeckel's genus ProcharybJis appears to be composed of immature or imperfectly known young specimens of Carybdea. It is not improbable also that future studies will show that Haeckel's Procharagma is actually Carybdea.

In some of the species of Carybdea the gastric cirri at the interradial comers of the stomach are in the form of branched tufts. The mature eggs are set free from the gonads and float in the gastric pouches, where they undergo a part of their development; but the larval stages remain practically unstudied.

A few physiological observations are reported of C. xnyiiiucdiiii In- Hc-rger and are discussed under the description of this species.

Carybdea marsupialis Pe'ron and Lesueur. Plate 58, figs, i to 5.

Medusa marsupialis, LINN£, 1758, Systcma Naturx, Ed. 10, p. 660; 1788 (Gmclin) tomus i, pars 6, p. 31^4. Carybdea marsupialis, P£RON IT LFSUEUR, 1809, Anna], du Mus. Hist. Nat. Paris, tome 14, p. ;-,;.

Charybdea marsufialis, CLAUS, 1878, Arbeit. Zool. Inst. Wicn, Bd. i, p. 221, 5 taf., fign. 1-48 (anatomy, histology). — HArcsri, 1880, Syst. dcr Meduscn, p. 442 (references to literature).

Bell prismatic, 4-sided, somewhat constricted near aboral apex, and with flat top. It is 40 mm. high and 30 mm. wide at level of velarium. The apex of bell, the pedalia. and the interradial ridges ot the exumbrella are besprinkled with numerous, quite regularly spaced, oval nematocyst-warts ot dull ocher-yellow color. The 4 interradial pedalia are each 17 mm. long and 10.5 mm. wide at their widest parts. The flexible, lash-like, filamentous parts of the tentacles are very contractile and range in length from 2 to 12 times as long as bell-height. These tentacles are hollow and regularly ringed with nematocysts.

The 4 perradially placed sense-clubs are each set in a niche almost covered by a gelat- inous flap. These sense-clubs are 5 mm. above the velar margin of the bell. Each sense- club has a median pair of large eyes with a doubly convex lens, and also 4 small, lateral ocelli, which lack lenses. All 6 eyes are directed inward so as to look into the bell-cavity, and are of ectodermal structure. Besides the 6 eyes there is a large terminal mass of entodermal cystalline concretions.

The velarium is supported by 4 bracket-shaped buttresses (frenulx) which bind it to the subumbrella in the radii of the sense-clubs. There are usually 3 (occasionally 4) branched, blindly-ending centripetal vessels in each octant of the velarium. These vessels branch quite complexly and irregularly, but do not anastomose. The base of the stomach is wide and flask-shaped, but the throat-tube is \erv narrow and with 4 simple, lanceolate lips. Altogether the manubrium is not more than one-third as long as the depth of the hell-ca\itv. There are 4 minute clusters of gastric cirri, one in each interradial corner of the stomach. These

508

MEDUSAE OF THE WORLD.

Synopsis of the Species of Carybdea*

	C. marsu- pialis.	C. rastonii = a variety of C. marsu- pialis ( ?)	C. xaymaca- na= a variety of C.marsu- pialis.	C. murraya- na=a varie- ty of C.m.ir- supialis (?)	C. alata.	C.pyramis= a variety of C. alata.	C. grandis= a variety of C. alata.	C. moseri= a variety or young stage - of C.grandis.
Size of bell in	4-sided,	4-sided,	Truncated	Square-	60 high, 50	Truncated	Truncated	High-dome-
mm.	prismatic.	prismatic.	pyramid	sided, flatly	wide. Sides	pyramid.	pyramid.	shaped, thin
	40 high,	35 high,	above; pris-	dome-like	pyramidal,	30 high,	230 high,	walled. So
	30 wide.	30 wide.	matic below.	top. 60 high,	apex	20 wide.	140 wide.	high, 47
			23 high,	50 wide.	rounded.		Thick walls.	wide.
			15 wide.
Form and size	Spatula-	Small, scalpel-	Scalpel-shap-	As in C. ras-	Spatula-	Very long,	Wide, flat,	Wide, flat
of pedalia in	shaped, flat.	sli j|H-(.l. One-	ed, flat, wider	tonii. One-	shaped.	narrow,	spatula-	as in C.
terms of	One-third	third to one-	than in C.	third long,	One-half	curved,	shaped.	grandis.
height of	long, one-	fourth long,	rastonii. One-	one- sixth	long, one-	scythe-	One-sixth	One-third
bell.	fourth wide.	one-fifth to	third to one-	wide.	fifth wide.	shaped.	long, one-	long, one-
		one-sixth	half long, one-			i long,	ninth wide.	fifth wide.
		wide.	fourth to one-			one-eighth
			third wide.			wide.
Length of	2 to 12	1.5 +	8±	2±	2 +	1 +	0.75 to I	i to 1.5
flexible ten-
tacles in
terms of
height of bell.
Number of	Six.	6	6	6	6	6	i to 3	4
eyes in each	2 median;						i median;	2 median;
sense -club.	4 lateral.						2 lateral.	2 lateral.
Form and	3, occasional-	2 branched	2 as in C.	6 profusely	3 branched	3 unbranch-	3 branched,	3 unbranch-
number of	ly 4, branch-	but not anas-	rastonii.	branched,	complexly,	ed, or only	but not anas-	ed.
velar canals	ed but not	tomosing.		but not anas-	but not anas-	some of them	tomosing.
in each oc-	anastomo-			tomosing.	tomosing.	branched.
tant of velar-	sing.					Non-anas-
ium.						tomosing.
Size and	Base wide,	Wide, flat,	Wide, flat,	Wide, flat.	Short with 4	Small, with :	Small, with	As in C
shape of	throat-tube	less than hall	with large,	with 4 short	simple lips.	large lips.	4 simple	grandis.
stomach.	slender and	as long as	lanceolate	lips.			lips.
	small.	bell-cavity.	lips.
Where found	Mediter-	Tropical	West Indies,	Coast of	Tropical	Tropical	Tropical	Tropical
	ranean.	Pacific.	tropical	Sierra Leone	Pacific.	Atlantic.	Pacific.	Pacific.
			Atlantic.	West Africa
				Depth of
				200 fathoms

* For C. aurifera see text.

cirri are brush-like, and in each cluster about 8 to 10 primary branches arise, and each gives off 2 to 3 lateral branches, each of which terminates in a brush of 10 to 13 filaments. There are thus 100 to 150 of these terminal filaments in each interradial cluster of gastric cirri. The gonads are 8 leaf-like expansions on both sides of the 4 interradial septa. They extend not quite to the velar margin or to the interradial edges of the stomach.

Bell and pedalia dull milky-ocher, due to the color of the exumbrella nematocyst-warts. Flexible parts of tentacles dull pink. Ocelli very dark brown, nearly black; basal branches of gastric cirri dull horny-brown.

The medusa is common in the Mediterranean, but its development remains unknown. Claus, 1878, gives a detailed account of its anatomy and histology. When young it apparently remains in deep water probably at or near the bottom, but when mature it swims upward to the surface.

Carybdea rastonii Haacke.

Charybdea rastonii, HAACKZ, :8S6, Zool. Anzeiger, Bd. 9, p. 554; 1887, Jena, Zeit. fur Naturwissen., Bd. 20, p. 591, taf. 35, fign.

1-15; 1888, Biol. Centralblatt, BJ. 8, p. 357.— VON LENDENFELD, 1888, Biolog. Centralblatt, BJ. 8, p. 218.— MAYER, 1906,

Bull. U.S. Fish Commission, vol. 23, Part 3, 1 903, p. 1134, plate i, figs, i-ic.— BICELOW, H. B., 1909, Mem. Mus. Comp.

Zool. at Harvard College, vol. 37, p. 17, plates I and 10. — MAAS, 1909, Abhandl. Akad. Wissen., Miinchen, Suppl. Bd.

i, Abhandl. 8, p. 41.

Char\bdeaarborifera (young medusa), MAAS, 1897, Mem. Museum Comp. Zool. at Harvard College, vol. 23, p. 86, taf. 14, fign. 7-10. Procharagma prototypus (young medusa?), HAECKEL, 1880, Syst. der Medusen, p. 436, taf. 25, fign. I, i.—Procharybdis cuboides,

Ibid., p. 439.

Bell nearly cubical, with flatly rounded top and nearly plane vertical sides. 35 mm. high, 25 to 30 mm. wide. Pedalia small, only one-third to one-fourth as long as bell-height, and

PLATE 57.

Fig. I. Carybdea xaymacana, young medusa. Nematocyst-warts so promi- nent in young medusa (fig. 5, plate 56) are beginning to disappear. Nassau Harbor, Bahamas, June, 1903.

Fig. 2. Tamoya haplonema, natural size. Mature medusa dredged from a depth of 2 fathoms off Brown's Point, Great Peconic Bay, Long Island, New York, September 5, 1902.

Fig. 2'. Tamoya haplonerna. Quadrant of bell-margin showing velar canals.

Fig. 2". Tamoya haplonema. Sense-club showing side that is directed inward toward the interior of the bell-cavity.

Fig. 2'". Tamoya haplonema. Side view of sense-club.

Fig. 3. Chiropsalmus rjiiaJrumanus, O.66 natural size. Fish Commission Laboratory, Beaufort, North Carolina. From the bottom off Beaufort entrance at a depth of 3 to 9 fathoms, July, 1904.

Drawn from nature, by the author.

MAYER

PLATE e?

CARYBDEID^E — CARTBDEA. 509

three-fifths as wide as long. Flexible lashes of tentacles 1.5 times as long as bell-height. 4 sense-clubs in niches 5 mm. above velarium. Each club with 2 large median and 4 small lateral eyes, and an entodermal lithocyst. Velarium wide with 4 perradial, subumbrella frenulae and 16 short, branched, non-anastomosing velar canals, 4 in each quadrant. Manu- brium flat, wide, less than half as long as depth of bell-cavity. 4 simple lips. 4 very small, interradial tufts of branched gastric cirri as in C. marsupialis.

8 leaf-shaped gonads along entire sides of the 4 interradial septa. Each gonad is widest near the stomach and tapers toward both ends. Flexible parts of tentacles and gastric cirri dull pink. It swims toward a light at night.

Gulf of St. Vincent, South Australia; Honolulu Harbor, Hawaiian Islands; Subig Bay and Nasugbu, Luzon, and Mausalay, Mindoro, Philippine Islands, in January. Common on surface. Probably widely distributed over the tropical Pacific.

The medusa begins to develop its gonads when the bell is only 1 1 mm. high and they are large in medusae 15 mm. high.

The youngest medusae found by Haacke had a pyramidal bell and an axial-canal above the stomach-cavity as if it might have been attached at one time to a scyphostoma nurse. Each sense-club had but 2 eyes, the median ones; and the 1 6 velar canals were simple and unbranched. C. arbortjera Maas, 1897, from Honolulu, is clearly the young of this species.

This small medusa may be distinguished by its cubical bell and small pedalia. It is closely related to the Mediterranean C. marsupialis.

The following are the dimensions (in millimeters) of a specimen obtained by the U. S. Bureau of Fisheries steamer Albatross in Subig Bay, Luzon, Philippine Islands, on the surface, January 6, 1908. Height of bell, 34 ; width ofjbell, 20; length of pedalium, 11; width of pedalium, 6.5; sense-clubs, 6 above the velar margin; flexible shafts of tentacles, contracted, 30 long. In this specimen the bell was unusually narrow.

Carybdea xaymacana Conant. Plate 56, figs. 5 to 7; plate 57, fig. I.

Charybjea xaymacana, CONANT, 1897, Johns Hopkins Univ. Circl., No. 132, p. 8, fig. 8; 1898, Mem. Biol. Lab. Johns Hopkins Univ., vol. 4, No. i, pp. 4, 7-57; figs. 1-16, 31-34, 36-43, 57-67, 69, 70, 72. — BERGER, E. \V., 1898, Jour. Comp. Neurol- ogy, Granville, vol. 8, p. 223, 5 figs, (structure of eyes); 1900, Mem. Biol. Lab. Johns Hopkins t'niv., vol. 4, No. 4, p. 1-84, 3 plates. — MAYER, A. G., 1904, Mem. Nat. Sci. Museum Brooklyn Inst. Arts and Sci., vol. i, plate 7, fig. 60.

Tamoya ftunctata (young medusa), FEWKES, J. \V., 1 883, Bull. Mus. Comp.Zool.at Harvard College, vol. 1 1, p. 84, plate I, figs. 4-6.

Bell 18 to 23 mm. high, 15 mm. broad. Sides vertical for two-thirds their height, above which they slope slightly inward. A slight concavity at top of bell. Pedalia flat and scalpel- shaped and between one-third and half as long as bell-height. The 4 tentacles are at least 8 times as long as the bell-height. The 4 sensory-clubs are situated each within a niche about one-seventh or one-eighth the distance from bell-margin to apex. Each club contains an ento- dermal, crystalline concretion and 6 ectodermal eyes; 2 of these eyes are large and median, 4 are small and lateral. These eyes are all on the centripetal side of the club, so as to look inward into the bell-cavity. The median eyes are each provided with a prominent lens, whereas the lateral eyes have no lenses. Velarium about one-seventh as broad as bell-diame- ter. 16 velar canals, 4 in each quadrant; these canals are forked at their ends, at times with more than 2 branches. Stomach flat and shallow. The throat-tube, which is well developed, with 4 large oral lobes, hangs down into bell-cavity a distance between one-third and half the bell-height; it is very sensitive and contractile and can be inverted into the stomach, The 4 tufts of gastric cirri are epaulet-shaped and of small size. Each tuft arises from a stalk-like base which projects from the subumbrella floor of the stomach. There are 8 leaf- like gonads.

Bell translucent, slightly pink or milky with bluish-purple nettling warts near the aboral apex of the exumbrella and bluish-purple tentacles.

This species was found by Conant in Kingston Harbor, Jamaica. I have obtained it in Nassau Harbor, New Providence Island, Bahamas, in spring and summer.

Good figures of the mature medusa are given by Conant, 1897-98.

Berger, 1900, finds that strong light, or darkness, inhibits the pulsation of this medusa. A sudden change in the intensity of the light acts as a stimulus. Removal of all 4 sense-

510

MEDUSAE OF THE WORLD.

clubs causes a short temporary "paralysis," but pulsation is soon resumed. Severance of the marginal nerve-ring in 8 places, so as to isolate the sense-organs from the tentacles, does not interfere with pulsation. The operation, however, causes the pedalia to bend inwardly by contraction. When the pedalia are cut off the medusa swims unnaturally, being unable to steer itself and turning in circles and somersaults. Removal of the perradial and inter- radial marginal ganglia produces paralysis of the pulsations.

When young the exumbrella of this medusa is regularly besprinkled with brown-colored, conspicuous clusters of nematocysts. When the bell is 4 mm. high it is pyriform, thin-walled, and the pedalia are merely short, flattened, swollen basal bulbs of the ringed tentacles. The velarium has no velar canals and there are no gastric cirri. The young medusa is abundant in Nassau Harbor, Bahamas, during the summer.

Carybdea aurifera Mayer.

CJiarybdea aurifera (young medusa), MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard College, vol. 37, p. 70, plate 25, figs. 81-83.

A young medusa was described from the Tortugas, Florida, in 1900, but in 1909 a much larger but yet immature specimen was found. In this large specimen the bell is 7 mm. long, 5 mm. wide at the velar margin, thin walled, and tapering to a blunt apex. The exumbrella

is besprinkled by large, wart-like clusters of nettle-cells. The 4 pedalia of the tentacles are 2 mm. long and the shafts of t^ie tentacles about the same length. These tentacle-shafts are each ringed by 7 to 9 rings of nematocysts. The 4 rhopalia are set in niches about I mm. above the velar margin. Each club bears I large, median and 4 small, lateral eyes. The velarium is wide, has well-developed, circular muscles and is supported by 4 perradial frenulae. There are 16 main velar

FIG. 328. — Carybdea aurifera, young medusa. From life, by the author, at Tortugas, Florida, July n, 1909. A, side view. B, oral view showing velar canals. C, gastric cirri. D, side view, and inner side of sense-club.

canals; the 8 adjacent to the frenulse are narrow and simple, but the 8 adjacent to the tentacles are wide and each gives off 3 or 4 finger-like processes. The manubrium is wide, 4-sided and nearly half as long as the height of the bell, with 4 simple lips. There are about 100 simple, tapering, unbranched gastric cirri. The most characteristic feature of this species is its uniform rich rosin or golden-brown color. It is a rare form and has been taken only twice in ten years in surface tows, in July, at Tortugas, Florida.

Carybdea alata Reynaud.

Carybdea alata, REYNAUD, 1830, Lesson's Centurie Zoologique, p. 95, planche 33, fig. I. — VANHOFFEN, 1908, Deutsche Sudpolar Expedition, 1901-03, Bd. 10, Zool. 2, p. 34, fign. 3, 4.

See synoptic table of species of Carybdea.

Bell 55 mm. high, pyramidal, with a rounded apex and rounded angles. Bell 42 mm. wide at margin and 17 mm. wide at base of rounded apex. The 4 pedalia are each 27 mm. long and 12 mm. wide at widest part. The rhopalia are 13 mm. above bell-margin. When the bell is 55 mm. high there are 6 wide dichotomously forked velar canals in each quadrant between successive pairs of tentacles. In medusae having a bell 60 mm. high, the forking of these canals becomes more complex and quite irregular, no two quadrants being alike. Thus

CARYBDEID.E — CARYBDEA.

511

it is probable that C. pyramis from the West Indies, C. obeliscus from the Cape Verde Islands, C. p/nlippina from the Philippine Islands, and C. granJis from the Paumotos Islands are only varieties or developmental phases of C. alata, the oldest species.

Carybdea alata var. pyramis Haeckel.

Charybdea pyramis, HAECKEL, 1880, Syst. der Meduscn, p. 440, taf. 25, fign. 5-8.

(?) Charybdea obt/iscus, HAF.CKEL, Ibid., p. 441.

(?) Carybdea alata, REYNAUD, 1830, Lesson's Centurie Zoologique, p. 95, planche 33, fig. I.

Bell about 30 mm. high and 20 mm. broad. A 4-sided truncated pyramid, the upper part being about one-third and the lower two-thirds as wide as the bell-height. A deep interradial furrow bordered by a pair of prominent ridges extends down the 4 sides of the exumbrella. The very long, narrow pedalia are lancet-shaped and about as long as the bell-height. The 4 perradial sense-clubs have each 6 eyes and are set in deep niches on the sides of the bell. Bell-margin displays 8 shallow lappets, the clefts being occupied by the 4 frenulae and the 4 pedalia. The 4 frenulae which support the wide velarium are 3-cornered and thick. 24 simple, 3-cornered velar canals, 6 in each quadrant. The stomach is not quite as wide as the bell-radius, and is shallow and quadratic. Neck large, 4-sided, pyramidal,

and separated from the stomach by a deep stricture. 4 large, 3-cornered lips with folded edges. Gonads 8 wide leaves with irregular, crenulated,free margins. This form is found in the tropical regions of the Atlantic.

Carybdea alata var. grandis Agassiz and Mayer

Cli<2r\bdfa grandis, ACASSIZ, A. and MAYFR, 1902, Mem. Museum Comp.

Zool. at Harvard College, vol. 26, p. 153, plate 6, figs. 26-31 . — Bl(.M.mv,

H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37. p. 17. ( ?) Charybdea grandis, BROWNE, 1905, Report Pearl Oyster Fisheries, Gulf of

Manaar, Suppl. Report No. 27, Roy. Soc. London, p. 157. (?) Bursarius ctiherra, LESSON, 1829, Voyage de la Coquillc Zoophytes,

p. 108, planche 14, fig. I. ( ?) Tamota bursaria, MAAS, 1903, Scyphomedusen der Siboga Exped., Monog.

u, p. 4.

This medusa may be identical with Lesson's Bur- sarius cytherea: but the latter is so vaguely described and figured that I feel obliged to omit it from serious con- sideration.

Adult medusa. — Bell high, pyramidal, with blunt apex. 230 mm. high, and 140 mm. wide. Gelatinous substance quite thick and of remarkably tough consis- tency. There are 4 interradial, wing-like pedalia, the broad sides of which extend outward in a radial direction.

medusa, after Agassiz and Mayer, in These pedalia are each about 40 mm. long, and 25 mm. Mjm.Mus. Comp. Zoo!, at Harvard wjde A wide canal extends through the substance of

each of them into the flexible portion of the tentacle,

which arises from distal end of pedalium. The flexible part of the tentacle is about 140 mm. long and its surface is ringed with transverse rows of nematocyst-cells. Each of the 4 per- radial sense-organs arises from a deep niche about 27 mm. above level of velarium.

The sense-organ is knob-shaped, mounted upon a short stem, and contains from I to 3 ectodermal ocelli and an entodermal concretion. In old medusa; there is usually a single, median ocellus in each sense-organ, but a young specimen 30 mm. in height had a large median and 2 small lateral ocelli. These ocelli are all directed as if to perceive objects within the bell-cavity. Velarium well developed and suspended by 4 mesenteries or frenulas in the radii of the sense-organs. 24 short, tree-like, non-anastomosing velar canals extend centnp- etally inward into the substance of the velarium. Manubrium short, 4 slightly recurved lips. There are 4 interradial crescentic areas of numerous short, gastric cirri, the horns of each crescent pointing centripetally. 4 wide perradial pouches, extending outwardly from the stomach, are separated one from another by 4 narrow interradial partitions, but are placed in communication one with another by means of lateral canals leading into the lumen of the

FIG. 329. — Car\bdea alata, var. grandis. Young

512 MEDUSA OF THE WORLD.

pedalia. The gonads consist of 8 leaf-like folds attached to the sides of the interradial septa and hanging free in the radial pockets.

Gelatinous substance of bell is hyaline; entoderm translucent and milky-white; gastric cirri and flexible parts of tentacles pink or yellow-pink; sensory knobs of rhopalia dull ocher in color; ocelli deep brown, almost black.

This species is by far the largest Carybdea known.

Found at Fakarava and at Anaa Islands, Paumotos Islands, South Pacific by the Alba- tross in October, 1899. A large swarm upon the surface at Anaa Island.

This medusa may be identical with the vaguely described Bursarius c \thcrcte Lesson, from New Guinea, or with Tamoya bursaria briefly mentioned by Maas, from the Malay Archipelago. Bigelow, 1909, believes that C. moscri is only the young of this medusa.

Carybdea alata var. moseri Mayer.

(?) — — , SEMPER, 1860, Zeit. fur wisscn. Zool., Bd. 13, p. 561, taf. 39, fig. 9.

(?) Charybdea philippina, HAECKEL, 1880, Syst. tier Medusen, p. 440.

Cliar\bdea tnoseri, MAYER, 1906, Bull. U. S. Fish Commission for 1903, vol. 23, part 3, p. 1135, plate I, figs. 2-2C.

This common Hawaiian Island medusa may be only a small variety, or a young stage, of Carybdea grandts. (See table of synopsis of the species of Carybdea.} It is probably identical with a medusa briefly mentioned and inadequately figured by Semper, from the Philippine Islands.

Bell 80 mm. high, 47 mm. wide, dome-shaped, with flat top and thin, uniform walls. Each sense-club has 2 large median and 2 small lateral eyes. The sensory niches are long, trans- verse, narrow, and 14 mm. above the velar margin. Pedalia spatula-shaped, flat, expanded, 25 mm. long, 17 mm. wide, 24 simple, unbranched, velar canals. Tentacles ringed, tapering throughout their length, hollow, and about 1.5 times as long as bell-height. Gonads not quite as long as the septa on which they are developed. Stomach small, flat, 4 simple lips, gastric cirri simple and unbranched. Honolulu, Hawaiian Islands.

Carybdea murrayana Haeckel.

Charybdea murrayana, HAECKEL, 1880, Syst. der Medusen, p. 442; 1881, Report Deep-sea Medusx Challenger Expedition, Zoo]., vol. 4, p. 93, plate 26, figs. i-io.

Bell 50 mm. wide, 60 mm. high, quadratic below, with flatly dome-like top. Pedalia narrow, tapering, flattened laterally, one-third as long as bell-height. Each sense-club has 2 large median and 4 small lateral eyes, as in C. marsuftialis. Velarium wide, with 48 pro- fusely branching, non-anastomosing canals. The 4 clusters of gastric cirri in the interradial corners of stomach are profusely branched, as in C. marsupiahs.

Off coast of Sierra Leone, west coast of Africa. Depth of 200 fathoms.

Distinguished from C. marsufaalis by its large number of velar canals.

Genus TAMOYA F. Miiller, 1859.

Tamoya, MULLER, F., 1859, Abhandl. Naturf. Ges. Halle, BJ. 5, p. I.— AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 174.— HAECKEL, 1880, Syst. der Medusen, p. 442.

The type species is T '. haplonema F. Muller of the Atlantic coasts of North and South America, south of Cape Cod.

GENERIC CHARACTERS.

Charybdeidae with 4 simple, interradial tentacles provided with pedalia. Stomach wide and deep; its 4 perradial sides flattened so as to present the superficial appearance of mesen- teries binding the 4-sided oesophagus to the subumbrella. There are 4 vertical, interradial, thread-like or brush-like bands of gastric cirri in the middle of interradial sides of stomach.

The so-called mesenteries of Haeckel are merely the flattened, perradial sides of the cruci- form stomach.

Haeckel's Tamoya bursaria and T. gargantna are too imperfectly known to be retained in scientific literature.

This genus is very closely related to, if not identical with, Carybdea, being distinguished only by its large stomach with its perradial mesenteries and its vertical clusters of gastric cirri. It may eventually prove necessary to unite this genus with Carybdea, for the differences between them are merely of an intergrading character.

CARYBDEID.E — TAMOYA, TRII'KDALIA. 513

Tamoya haplonema F. MUUer. Plate 57, figs. 2 to 2'".

Tamoya haflonema, MULLER, 1859, Abhandl. Naturf. Ges. Halle, Bd. 5, p. I, taf. I, 2. — AGASSIZ, L., 1862, Cunt. Nat. Hi

vol.4, P- '74' — HAECKEL, 1880, Syst. der MI,|UM n, ['.443. — BROOKS, 1882, Studio Juhns Hopkins Univ. Biol. Lab., vol. 2, p. 138. — VON LENDENFELD, 1884, Proc. Linnean Soc. New South W.do, vol. 9, p. 245. — MAYEK, 1904, Memoirs Nat. Sci. M'i nun Id •">!. I ui In .t. Art and Sci., vol. i, p. 28, plate 7, figs. 60-64.

Tamoya prismatita, HAECKEL, Ibid., p. 44;.

C.arybjra (Tamoya) haplontma, FrwKr.s, 1889, Report U. S. Cummis. Fish and Fisheries for 1886, p. 526.

Bell 90 mm. high, 55 mm. wide, with vertical sides, and relatively flat top. Exumhrella surface thickly covered with white, wart-like clusters of nematocysts. 4 pedalia, 30 mm. long, flat, spatula-shaped, and sharp-edged. Tentacles 90 mm. long, hollow, very flexible and bearing regularly spaced rings of nematocysts that are capable of inflicting a severe sting to the hand. The sensory-clubs have 2 large median and 4 small lateral eus, all being upon the inner side ot the bulb. The large eyes are provided with prominent convex lenses and are ectodermal. There is a large terminal mass of concretions of entodermal origin.

The velarium is well developed and there are 10 dendritic velar canals in each quadrant, which terminate in numerous, non-anastomosing branches. The nerve-ring running from the base of each pedalium to the sensory-clubs is distinctly visible as a white-colored cord. The stomach extends about a third of the distance from inner apex to level of velarium, and there are 4 slightly recurved lips. Gastric cirri short and numerous.

The 8 genital organs are curtain-like sheets with frilled edges, which project from the 4 interradial septa into the perradial gastrovascular pouches of bell on either side. In old specimens the gonads are so large that their free edges overlap beyond the central line of each perradial stomach-pouch.

Gelatinous substance of bell transparent. The long, flexible tentacles are milky-yellow, often with a faint purple hue. There are large, white, wart-like clusters of nematocysts over the pedalia and velarium. The genital organs are milky-yellow, the eyes dark brown.

This medusa is exceedingly active, the gelatinous substance of its bell is tough and rigid.

Tamoya haplonema is widely distributed, having been found on the coast of Brazil, in the West Indies, at Beaufort in North Carolina, and in Great Peconic Bay, and Branford Harbor, Long Island Sound, New York, in the autumn. Our figures were obtained from a specimen captured at the last-named place early in September, 1902. None was found upon the surface in Great Peconic Bay, but all were brought up in dredges from the bottom at depths of a fathom or more.

Haeckel's Tamoya prismatica from the West Indies is apparently identical with T. hap- lonema. It is described as follows:

Bell 80 mm. high, 40 mm. broad, pyramidal, and 4-sided. The pedalia are longer and narrower than in T. haplonenia. They are wedge-shaped, and 3 times as long as bio.ul. and about half as long as bell-height. In their upper parts they are 3-sided, but below they are 2-sided with small meridional wings. Velarium VITV wide, with numerous, narrow, branching canals. Stomach large, occupvJng upper third of bell-cavity. Throat-tube about as large as stomach, 4 prominent lips. Color (?) Marginal sense-organs (?)

This form is found in the West Indies. It is probably only a variety of T. haplonema.

Genus TRIPEDALIA Conant, 1897.

Triptiialia, CONANT, 1897, Johns Hopkins Univ. Circulars, No. 132, p. 9; 1898, Mem. Johns Hopkins Univ. Biol. Lab., vol. 4, No. I, p. 5.

The type species is T. cystop/iora, described by Conant from Kingston Harbor, Jamaica.

GENERIC CHARACTERS.

Carybdeids with 4 interradial groups of tentacular pedalia, each tentacle being mounted upon a separate, unbranched pedalium which arises from the bell-margin. Velarium with canals and with 4 perradial frenulae. No hernia-like sacs project into the bell-cavity from the mam stomach-pouches of umbrella.

This genus is very closely related to Cluropsalmus, but the pedalia themselves do not branch, but each pedalium of each cluster arises separately from the interradial corner of the

514

MEDUSAE OF THE WORLD.

bell-margin. In Chiropsalmus, on the other hand, each of the 4 pedalia gives rise to side branches which bear tentacles. Moreover, in Tripedalia there are no subumbrella, hernia- like, gastric diverticula as in Chiropsalmus.

Tripedalia cystophora Conant.

Tripedalia cystophora, CONANT, 1897, Johns Hopkins Univ. Circulars, No. 132, p. 9, fig. 9; 1898, Mem. Johns Hopkins Univ. Biol. Lab., vol. 4, No. I, pp. 5, 22; figs. 17-30, plates I, 2, 5, 7, figs. 44, 45, 53-56, 68, 71.

Bell cubical, with edges slightly rounded; 12 mm. high, and of about 15 mm. wide. There are 4 interradial groups of pedalia, each group consisting of 3 distinct, separate pedalia, each one of which arises from the bell-margin and gives rise to a single tentacle. The pedalia

are flattened and resemble a slender knife-blade, and are about half as long as the bell-height. The 12 tentacles are each about 2.5 times as long as the pedalia. 4 sense-clubs are situated in niches at about one-fifth or one-fourth the height of bell above mar- gin. Each sense-club has 2 large, median and 4 small, lateral eyes and a terminal lithocyst. The median eyes have doubly convex lenses. Velarium about one-sixth as broad as bell-diameter. There are 24 simple, unforked velar canals, 6 in each quadrant. These velar canals are triangular in outline, and the 8 adjacent to the 4 frenulae are only half as wide as the others. Stomach wide and shallow, butthethroat- tube is lono- and extends downward in some cases to

O

bell-margin; cruciform in cross-section, with 4 well- developed, oral lobes in the radii of the sense-organs. There are 15 to 21 organs, resembling lithocysts, in the gelatinous walls of the manubnum; each con- sists of a round or oval sac lined with ciliated cells which keep in motion and bear up an irregular,

FIG. 170. — Tnhedalia cystophora* i IT > TI

coarsely granulated concretion. These organs are

scattered irregularly through the gelatinous substance and are probably of entodermal origin. The small, tapering, gastric cirri are brush-shaped and spring from 4 short stalks in the inter- radial corners of the stomach. There are 4 wide, perradially situated, gastrovascular pouches in the umbrella, which are separated by 4 interradial septa; but these septa are incomplete in the regions of the pedalia, and thus the 4 stomach-pouches are placed in com- munication one with another, as in other Charybdeidae. The gonads are 8 leaf-like sheets attached to the sides of the 4 interradial septa and projecting out into the 4 perradial stomach-pouches. The medusa is light yellowish-brown, the gonads being of the same color.

Figure 330 shows a mature female, 4 times natural size, drawn from nature, by the author. In order to illustrate their shape, the lips are shown twisted 45° from their natural position.

This species is found in Kingston Harbor, Jamaica, in great abundance during the sum- mer among the mangrove roots ot the islands in a shallow, muddy lagoon on the western side of the harbor, north of Port Henderson. It disappears in winter.

The dimensions of the mature specimen here figured are as follows: Bell 12 high, 15 mm. wide. Pedalia 5 mm. long, 2.1 mm. wide. Rhopalia 2.25 mm. above velarium margin. Stomach 5.5 mm. wide, j mm. long. The gonads were mature and the gastrovascular space filled with swimming planulae. This medusa was captured on May 24, 1909.

Conant succeeded in obtaining females having embryos within their gastrovascular pouches. The embryos were thrown out into the water as free-swimming planulse, which settled down on the bottom and sides of the aquarium in a day or two and quickly developed into small Scyphostomae with mouth and typically with 4 tentacles and 4 taeniolae, although 3 and 5 tentacled specimens were not uncommon. In this condition they lived for 3 weeks without essential change. I find that many, but not all of the planulse, are besprinkled with dark brown pigment-spots which are scattered over the ectoderm of the narrow posterior end of the larva.

PLATE 58. All figures are of Carybdea marsupialis.

Fig. i. Mature medusa, 1.25 times natural size. Naples Zoological Station,

December 5, 1907.

Fig. 2. Sense-club seen from exumbrella side. Fig. 3. Side view of sense-club.

Fig. 4. One of the velar canals showing its branches. Fig. 5. One of the gastric cirri showing its brush-like terminal branches.

Drawn from life, by the author.

MA\ •

CARYBDEID.E — CHIROPSALMUS. 515

Genus CHIROPSALMUS L. Agassiz, 1862.

Chiropsalmus, AGASSIZ, L., 1861, Cent. Xat. Hist. U. S., vol. 4, p. 174— HAECKEL, 1880, Syst. der Medusen, p. 446.— VON LEN- DENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 247.

GENERIC CHARACTERS.

With 4 interraclial, branched pedalia which give rise to a number of tentacles. 4 wide perradially situated stomach-pockets in the subumbrella, and each of these gives rise to finger-shaped, unbranched, hernia-like pouches which project into the bell-cavity. Wide, marginal pouches and numerous canals in the velarium. 8 leaf-shaped gonads.

The type species of this genus is Chiropsalmus quaJrumanus, described as Tamoya quaJrumanus by F. Miiller, 1859. This species is found in the warmer waters along the Atlantic coasts of North and South America south of Cape Hatteras.

Chiropsalmus quadrumanus L. Agassiz.

Plate 57, fig. 3.

Tamoya quadnimanus, MULLER, F., 1859, Abhandl. Naturf. Gesell, Halle, Bd. 5, pp. l-n, taf. 2, 3, fign. 18-32. Chiropsalmus quadrumanus, ACASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 174.— HAECKEL, 1880, Syit. dcr Medusen, p.

+47 .— VON LENDENFF.LD, 1884, Proc. Linn. Soc. New South Wales, vol. 9, p. 248.— CONANT, 1898, Mem. Johns Hopkins

Univ. Biol. Lab., vol. 4, No. I, p. 4

Bell dome-shaped, about 140 mm. wide and 100 mm. high. 4 large, hand-shaped pedalia, the 7 to 9 finger-like branches of which give rise each to a single, long, slender tentacle. 7 to 9 tentacles thus arise from each pedalium. These tentacles are hollow and flexible, and are covered with numerous, closely set rings of nematocysts. A large axial-canal extends through the pedalium and gives off" branches, one to each tentacle. The 4 sense-organs are situated within 4 covered niches upon sides of bell at about one-sixth the distance from margin to apex. There are 6 ectodermal eyes upon the sense-club, 2 large median and 4 small lateral. Velarium very wide with 1 6 large branched pouches which extend into it from the 4 main, gastrovascular spaces of the bell. The 16 velar pouches give rise in turn to numerous small, branching canals which ramify through the velarium. Stomach wide and globular, the mouth surrounded by 4 large, triangular lips. 4 wide, perradial pouches extend from stomach into wall of bell; each of these pouches gives rise to 2 finger-shaped, hollow, hernia-like sacs which project from the subumbrella side into the cavity of the bell; these 8 sacs are situated very near base of stomach. There are 4 interradial, crooked, crescent-shaped rows of gastric cirri on inner walls of stomach.

This species was found by Miiller at Desterro, Santa Catharina, Brazil, and later it was obtained by H. V. Wilson at Beaufort, North Carolina, where it is quite abundant on the sea-bottom, about a mile off shore, though sometimes found within the harbor itself.

Chiropsalmus buitendijki Horst. Chiropsalmus buitendijki, HORST, 1907, Notes from the Leyden Museum, vol. 29, No. 2, p. 101, plate 2, figs. 1-6.

This species from the harbor of Batavia, Java, is distinguished by its 8 long, simple, finger-shaped, subumbrella pocket-arms nearly as long as the depth ot the bell-cavity, so that they almost touch the velarium. The pedalia also have 5 or 6 lateral branches arranged, judging from Horst's figure, in a linear series on the outer side of the main shaft, the largest branch being nearest the bell. In other species of Chiropsalmus the side branches ot the pedalia are irregularly arranged.

In other respects the Javanese medusa resembles the other species of Chiropsalmus. Bell cubical, 65 to 70 mm. high and wide, with a slightly arched apex. Main shafts of pedalia sickle-shaped, about half as long as bell-height, and laterally compressed. The 5 or more lateral branches all arise from the abaxial side of the pedalium and form a decreasing series, the smallest being outermost. The rhopalia are in niches about one-fihh the distance between velarium and bell-apex. Each club has 2 large median and 4 small lateral eyes. The velarium is wide, has 4 frenulae, and 16 dendritically branched velar canals. Bell transparent, flexible parts of tentacles of a rosy hue. In its simple finger-shaped processes ot the subumbrella floor of the bell this species resembles the American Chiropsalmus quadrumanus to which it is closely related.

516

MEDUSAE OF THE WORLD.

Chiropsalmus quadrigatus Haeckel. Chiropsalmus quadrigatus, HAECKEL, 1880, Syst. der MeJusen, p. 447.

The following description is based upon a study of six specimens obtained in a seine

by the U. S. Bureau of Fisheries steamer Albatross among the Phil- ippine Islands, from January to June, 1908.

Bell dome-like and 4-sided, with an evenly rounded, aboral apex. 70 to 100 mm. high, 80 to 100 mm. wide at level of velarium. There are 4 hand-shaped, interradial pedalia, laterally flattened, which arise from the sides of the bell at a short dis- tance above the velar margin. These pedalia are about 30 mm. long and n mm. wide, and each bears 5 to 9 finger-shaped terminal projections which give rise to an equal number of long, flexible, hol- low tentacles. These tentacles are thickly but somewhat irregularly ringed with nematocysts. They vary in length, but the longest when contracted are about 150 mm. long. The pedalia of a medusa 100 mm. wide were each 47 mm. long and 21 mm. wide.

The 4 perradial sense-clubs are set within covered niches in thesides of the bell about 14 mm. above the velar margin. Each sense-club con- tains an entodermal, terminal, abax- ial mass of concretions and on its inner side are 6 eye-spots. The 2 median eyes have each a prominent convex lens, but the 4 smaller, lat- eral eyes are merely pigmented ocelli. The eyes are arranged so as toviewobjects withinthe bell-cavity. The velarium is 13 mm. wide and supported by 4 bracket-like perradial frenulae. There are about 50 dendritic, non-anastomosing velar canals, 12 to 15 in each quadrant. The velarium is diaphragm-like and does not hang downward beyond the velar margin but stretches flatly across tending to close the opening of the bell-cavity.

The wide central stomach is only about 20 mm. long and there are 4 lanceolate lips with entire, simple margins. The 4 perradial sides of the cruciform stomach are much flattened and form the so-called "mesenteries" of Haeckel, bridging across, bracket-like, between the subumbrella and the 4-sided cesophagus. 4 pairs of gastric saccules arise from the perradial sides of the stomach and project downward into the bell-cavity (c. fig. 331). Each saccule is laterally flattened, cock's-comb-shaped, with an irregularly notched margin, and is about 20 mm. long and 1 1 mm. wide. A solid, gelatinous projection extends downward so as to fill the greater part of the cavity of each gastric saccule.

There are 4 long, interradial bands of gastric cirri marking the borders of the central stomach. These cirri are fusiform, simple, sharp-pointed, and unbranched and arise in 4 or 5 rows. Each cirrus is about 3 mm. long.

FIG. 331. — Chtropsolntus quadfisafus Haeckel, side view of half-grown medusa, half natural size. Drawn by the author, from a preserved specimen collected by the Albatross. A, enlarged side view of sense-club. B, inner side of sense-club.

C, oral view of stomach showing the 4 lips and 8 gastric sacs.

D, enlarged view of gastric cirri. E, side view of a pedalium with all but one of the tentacles cut across.

CARYBDEID.E — CHIROPSALMUS.

517

The peripheral, gastrovascular system consists in the usual 4 wide, perradial stomach- pouches, separated by 4 narrow, interradial septa, which are interrupted at the point of origin of each pedalium where a canal extends downward from the adjacent stomach-pouches and branches in finger-like ramuli leading into the tentacles of the pedalium. The 50 or more velar canals have already been described. The 8 leaf-like gonads are well developed and resemble those of Gary bdea but are not yet mature. They arise on both sides of each inter- radial septum and project into the wide, perradial stomach-pouches.

The bell is milky-yellow in formation and there are traces of a dull purple-pink coloration in the tentacles. The ocelli are dark brown.

I am informed that this medusa is abundant in Subig Bay, Luzon, Philippine Islands, where it is captured in seines. The natives are said to preserve it in vinegar, and when so prepared it is sold in the markets for food.

In the young medusa having a bell 18 mm. high and 20 mm. wide, there are only 4 or 5 tentacles on each pedalium and the subumbrella saccules have not begun to develop, nor is there any visible trace of the gonads. The abaxial finger of each pedalium is longest, and the 3 others are evidently of more recent development, are very short, and lie nearer the velar margin. The longest (abaxial) tentacles are about 7 mm. long when contracted, and the axially placed younger tentacles are shorter. The perradial brackets of the velarium are beginning to develop and there are about 7 irregularly but simply branched velar canals in each quadrant.

Haeckel, 1880, describes a somewhat larger young specimen from Rangoon, Indian Ocean. The medusa is common among the Philippine Islands.

I am told that this medusa grows to be about 150 mm. in diameter, although the largest specimen in the Albatross collection is only 100 mm. wide, but appears to be mature. It is found swimming in shallow water near the shore. It is very closely allied to the Atlantic C. qvaJrumanus, but may be distinguished by its laterally flattened cock's-comb-shaped gastric saccules, those of C. quadrumanus being finger-shaped.

The following is a record of specimens of Chiropsalmus quadrigatus obtained by the Albatross in 1908 in the Philippine Islands:

Locality.	Date.	Height of bell in mm.	Width of bell in mm.	Number of tentacles upon each pedalium.	Remarks.
Cataingan Bay, Masbate, near shore.	April 1 8	49	55	6, 6, 7, 7	Immature. The 8 gastric saccules only beginning to
					appear.
Do.	April 1 8	5'	51	8, 6, 7, 5	Do.
Do.	April 1 8	40	20	6, 5, 6, 6	Do.
Subig Bay, Luzon. Caught in a seine.	January 7	18	2O	4> 4> 4. 4	No gastric saccules and no gonads.
Do. See fig. 331	January 7	70	80	9. 5. 8, 8	With well-developed but immature gonads. With large cock's-comb-shaped gastric saccules.
Mausalay, Mindanao.	June 4	97	100	8O 0 0 t Of Of O	Apparently mature.

Chiropsalmus zygonema Haeckel.

Chiropsalmus zygontma, HAECKEL, 1880, Syst. der Mcdusen, p. 641.

Bell 4-sided, pyramidal with a truncated apex, 60 mm. high and 40 mm. wide, including height of velarium. The 4 pedalia are leaf-shaped, each with only 2 short, asymmetrical, gelatinous, finger-shaped branches which give rise to long, lash-like tentacles. In all, there- fore, there are but 8 tentacles. Stomach round and sac-like, oesophagus small with 4 lappets, though only half as long as stomach. 4 interradial bow-like areas of gastric cirri in stomach wall. The stomach gives rise to 4 perradially situated pouches, on both sides of the entrance to each of these pouches near the stomach are 2 very small, oval pouch-arms — 8 in all.

This species is found off the Argentine coast, South America. It differs from all other species of Chiropsalmus in its simple, 2-pronged pedalia, and in the very small finger-like pouches ot the stomach. The velarium and gonads are similar to those of C. quadrumanus.

518

MEDUSA OF THE WORLD.

Genus CHIRODROPUS Haeckel, 1880.

Chirodropus, HAECKEL, 1880, Syst. der Medusen, p. 447.

The type species is Chirodropus gorilla Haeckel, of the Atlantic coast of equatorial Africa.

GENERIC CHARACTERS.

Carybdeidae with 8 branched, or feathered, sac-like projections which extend from the 4 perradial stomach- pouches into the bell-cavity. The free margins of the gonads show grape-like swellings. With 4 hand-like pedalia.

This genus resembles Chiropsalmus, but is distin- guished by its branched hernia-like pouches in the bell- cavity, whereas in Chiropsalmus these projections are unbranched; moreover, in Chiropsalmus, the free mar- gins of the gonads are simple and entire, whereas in Chirodropus they are broken up into grape-like clusters of swellings.

Chirodropus gorilla Haeckel.

Chirodropus gorilla, HAECKEL, 1 880, Syst. der Medusen, p. 448, taf. 26, fign. 1-8.

Bell dome-shaped, evenly rounded above and in- cluding the velarium, which hangs downward, 150 mm. high and 120 wide. Sides rounded; the sculptured angles usually seen on surface of exumbrella in Charyb- deidae are very poorly developed.

The 4 interradial pedalia are hand-like, asymmet- rical and hardly one-fourth as long as bell-height. Each pedalium gives rise to 9 long, narrow, tapering gelati- nous finger-like processes, each bearing a long, flexible, tapering tentacle longer than bell-height. Thus there are 36 tentacles in all.

The 4 perradial sensory niches are deep and heart- shaped. They are set in the sides of the bell at a some- what higher level than the pedalia and are about 60 mm. above velar margin. The sense-club is mounted upon a slender stalk. Number of eyes ( ?)

Below the marginal nerve-ring are 16 gelatinous lappets which form an integral part of the wide velarium which projects downward. The 16 lappets are cleft in the 4 interradii and in the 8 adradii, and are divided by the 4 perradial frenulae. The 8 lappets flanking the 4 frenulae are about 1.5 times as long as the 8 which flank the 4 interradial pedalia. These lappets contain diverticula of the perradial stomach-pouches and each lappet-pouch gives rise to about 6 dendritically branched velar canals, which only occasionally anastomose and which extend outward nearly to margin of velarium, running mainly parallel one to another.

Each perradial stomach-pouch gives rise to a pair of elongate, tapering, hollow processes, which project downward into the bell-cavity and bear numerous finger-like side processes, all of which arise from inner (axial) side of main process. These processes are thus much more complex than the simple finger-shaped ones of Chiropsalmus. Central stomach large and urn-shaped, 4-sided, bound to subumbrella by 4 perradial mesenteries. There are 8 dendritic, digestive glands, a pair on either side of each perradial corner of stomach-cavity. The 4 pairs of gonads are attached to the subumbrella sides of the 4 interradial septa, as in other Carybdeidae. Their free outer margins bear grape-like clusters of swellings. The only specimen studied by Haeckel was a male, found at Chenchozo Loango, Lower Guinea, about 5° S. lat. West coast of Africa. Described in detail by Haeckel who is the only natur- alist who has seen the medusa.

FIG.

332. — Chirodropus gorilla, after Haeckel, in Das Syst. der Medusen.

CARYBDEIOE — CHIRODROPUS. 519

Chirodropus palmatus Haeckel. Chirodrofus palmatus, HAECKEL, 1880, Syst. der Medusen, p. 448.

This is possibly only the young of a variety of C. gorilla being smaller, and only 70 mm. wide and 100 mm. high, including the suspended velarium. The 2 pouch-arms which project into the bell-cavity from each perradial stomach-pouch are fused together in their upper two-thirds, leaving only their lower thirds free. They bear numerous filaments, as in C. gorilla. Finally, each pedalium bears 21 fingers instead of 9, as in C. gorilla.

A single specimen is described by Haeckel from preserved material found near St. Helena off the west coast of Africa.

We can not be sure that this form is distinct from C. gorilla until we know the normal limits of variability of the latter species, and it seems probable that there is but a single species which is somewhat variable in the number of tentacles, etc.

Order STAUROMEDUSJE.

Lucernarid* (in part), JOHNSTON, 1847, British Zooph., p. 244, id cd.

Stauromtdusit, HAKI KKL, 1880, Syst. dcr Meduscn, p. 363. — GOETTE, 1887, Abhandl. zur Entwickelungsgesch. dcr Thierc, Heft 4, p. 64. — MAAS, 1906, Fauna Arctica, Bd. 4, Lfg. 3, p. 499; 1907, Ergcb. Fortschitte dcr Zoologic, Bd. I, pp. 194, 198. Lacernaridit, GROSS, 1900, Jena. Zeit. fur Natunv., Bd. 33, p. 611. — KASMANHW, 1901, Zcit. fur wissen. Zool., Bd. 69, p. 287. Lucernaria, CLARK, 1863, Boston Journ. of Nat. Hist., vol. 7, p. 531.

Neglecting for the moment to consider the family Tesseranthinae Haeckel, the Stauro- medusae constitute a unitary group of sessile Scyphomedusae which are attached to objects by means of an adhesive pad at the extremity of the aboral stalk of the bell. The bell-margin usually exhibits 8 adradial lobes, the pointed ends of which terminate in clusters of hollow knobbed tentacles; although in Capri a we find that these tentacles are not knobbed, and in the genus Stenoscyphus there are no marginal lobes, while in ].if>kt-a there are no tentacles and the lobes are perradial and interradial, not adradial.

In the 8 perradial and intenadial notches between the marginal lobes we may find a knobbed tentacle, which may be metamorphosed into an adhesive organ serving as a sort of anchor. In the genera Luniinnm. A ' ishinmiyea, Craterloptius, C^ifriii, and /,;/>/•«;, however, these anchors are not found. The central stomach gives rise typically to 4 perradial pouches which are partially separated one from another by 4 interradial septa, but these pouches communicate one with another at the margin, thus forming a peripheral ring-sinus. The arms, or marginal lobes, are hollow, as are also their knobbed tentacles. There are 4 interradial septa in the central cavity of the aboral stalk or peduncle; and these partitions may fuse in the center, thus inclosing 4 separate perradial cavities in the stalk as in Haliclvstus. The gonads, which are developed in the entoderm of the subumbrelia, are typically interradial and more or less horse-shoe-shaped with the free ends of the horse-shoe directed outward; but often the horse-shoe is cleft in the middle, giving 8 adradial, crescentic gonads. There is a mar- ginal ring-muscle in the subumbrelia winch may be entire or divided into 8 separate perradial and interradial sectors. Centripetal to this ring-muscle system are the radial muscles. The stalk also has a system of 4 intenadial, longitudinal muscles. As in scyphostoma larvae the 4 interradial septa of Stauromedusae are not simple, solid-walled partitions, but each contains a funnel-like pit. hvitt with ectoderm, which dips downward from the subumbrelia thus hollowing each partition. These funnel-cavities contain longitudinal muscles which extend downward even to the aboral end of the stalk itself.

Clark, 1863, and after him Gross, 1900, have made careful studies of the internal anatomy of the sessile Stauromedusae. They conclude that we may divide these forms into 2 families, the Eleutherocarpidae with 4 simple, perradial stomach-pouches, and the Cleistocarpidae in which the neighboring halves of the adjacent gonads unite at their distal ends in the radii of the corners of the mouth. Thus the gonads become united by a transverse, circumferential mem- brane, which divides each of the 4 perradial stomach-pouches into 2 spaces, an outer and an inner, the oral or inner one of which forms a cul de sac or confined space which contains the gonads and opens at the axial end into the gastric cavity. The genera Haliniocyat/ius, Cra- terlophus, and Dffastruni are examples of the Cleistocarpidae, while Stenoscyphus, Kislnnouyea,

520

MEDUSAE OF THE WORLD.

Caprla, Llpkea, Lucernaria and Haliclystus represent the more simply organized Eleuthero- carpidae. A clear understanding of these relations can best be obtained from a study of the figures by Gross, 1900 (Jena. Zeitsch. fiir Naturwissen., Bd. 33, p. 613, taf. 23, 24). Being internal characters, I have not made use of them in the classification of the Stauromedusae.

As one would expect in sessile animals the Stauromedusae show evidences of degeneration, loss of marginal lobes or of tentacles; and in none of them do we find the lithocyst-bearing

Gelatinous substance '.:.'-:"-:-:':'.::::.0.-V.:

'

\ Nfc

Im. J

FIG. 332^. — Median longitudinal perradial sections and cross-sections of Stauromedusse. Somewhat diagrammatic, after Gross.

A. The internal anatomy of the Cleistocarpida; illustrated by Cralerlophus leihys.

B. The internal anatomy of Eleutherocarpida1 illustrated by Haliclystus. The cross-partition, or claustrum (C), is

found in the Cleistocarpidae but is absent in the Eleutherocarpidae.

In both figures: C, transverse partition spanning between gonads; ex, outer chamber; fc, funnel-pits containing longitudinal nucleus; g, gonads; gt, gastric cirri; Im, longitudinal muscles; st interradial septa.

sense-organs seen in all other orders of Scyphomedusae. Eyes and "otocysts" are absent in the Stauromedusae, and pulsation is not exhibited by the sessile forms.

There is reason to believe that the Stauromedusae are the most degenerate of all Scypho- medusae and are to be regarded as sexually mature Scyphostomae (see Kassianow, 1901; Goette, 1887). Their degeneracy is amply accounted for by their sessile mode of life; Hornell, 1883 (Natural Science, London, vol. 3, p. 204), and Hurst (Ibid., p. 209) believe that they are

STAUROMEDUS.B.

521

descended from some more highly organized forms of Scyphomedusae. Their chief reasons for this belief lie in the facts that in the Lucernaridae the marginal anchors (colletocystophores) are highly variable and may therefore be vestigial organs. Moreover, in Lucernaria cam- panulata the marginal anchors exist in the very young medusa but disappear as development proceeds and are not found in the adult. This evidence, although meager, supports the

Synopsis of the Genera of Stauromedusa.

	Tesseranthina;: Pelagic	Lucernarinx: Attached medusa?, usually with hollow, knobbed
	medusa: with solid,	tentacles, and typically with marginal lobes.
	tapering, non-knobbed
	tentacles, and without
	marginal lobes.
	Tesseraria = Tessera +	Depastrum =	Stenoscyphus.	Lucernaria.	Kishinouyca.
	Tesserantha + Tesseraria	Depastrella +
	Haeckel.	Depastrum
		Haeckel.
Number and char-	8 solid, tapering, without	Hollow, ending in	An anchor in each	None.	None.
acter of perradial	terminal knobs.	nettling knob.	interradius and
and interradial		I to 3 tentacles	perradius.
tentacles.		in each cluster.
Character of adra-	Similar to perradial ten-	Similar to per-	A cluster of hol-	8 clusters of hol-	As in Lucernaria.
dial tentacles.	tacles.	radial and inter-	low, terminally-	low, terminally-
		radial, but with	knobbed tenta-	knobbed tenta-
		more tentacles in	cles in each ad-	cles.
		each cluster.	rajius.
Other tentacles.	Similar to perradial ten-	None.	None.	None.	None.
	tacles.
Cleistocarpidtf are		C	E.	E.	E.
indicated by C,
Eleutherocarpidte
byE.
Gonads.	4 interradial, horse-shoe	As in Tesseraria.	Adradial.	8 adradial (4 cleft	As in Lucernaria.
	shaped.			in intcrradii).
Stalk at aboral pole	An aboral projection	An aboral stalk	A stalk with 4	Singlc-chamberec	With 4 perradial
of bell, serving for	which docs not serve for	serving to attach	perradial cham-		chambers.
attachment.	attachment Medusa	the medusa.	bers.
	pelagic.
Marginal lobes of	None.	8 adradial sinuos-	None.	8 adradial lobes.	8 adradial.
bell.		ities.
	Luccrnarinije: Attached medusx, usually with hollow, knobbed tentacles, and typically
	with marginal lobes.
	Haliclystus.	Halimocyathus.	Craterlophus	Capria.	Lipkea
			Halimocyathus ( ?)
Number and charac-	8 anchors.	8 anchors.	None.	None.	None.
ter of perradial ten-
tacles.
Character of adradial	As in Lucernaria.	As in Lucernana.	As in Lucernaria.	A row of basally	None.
tentacles.				webbed, finger-
				shaped, unknobbed
				tentacles.
Other tentacles.	None.	None.	None.	None.	None.
Cleistocarpida; are	E.	C.	C.	E.	E.
indicated by C,
F.leutherocarpids by
E.
Gonads.	As in Lucernaria.	4 interradial.	8 aJradial.	8 adradial.	4 interradial (?)
Stalk at aboral pole of	With 4 perradial	With 4 perradial	With 4 perradial	Single-chambered.	Single-chambered.
bell serving for at-	chambers.	chambers.	chambers.
tachment.
Marginal lobes of the	8 adradial.	8 adradial.	8 adradial.	8 adradial.	Eight; 4 perradial
bell.					and 4 intrrraji.il.

522 MEDUSA OF THE WORLD.

view that the Stauromedusae are degenerate, and, indeed, degeneracy would very probably result from their sessile condition.

The Tesseranthinae, known only through the works of Haeckel, who alone has observed them, appear to be pelagic and are said to differ from other Stauromedusae in having solid, tapering, non-knobbed tentacles, and in lacking marginal lobes. Their relationship to the Stauromedusae is uncertain. Only 4 specimens have ever been taken and these are described by Haeckel from preserved material. It will be well to suspend judgment in respect to their structure, relationship, and development until more specimens have been studied.

The sessile Stauromedusae are creatures of cold seas. None is known from the tropics. They are littoral forms and attach themselves to Fucus, Zostera, and other seaweeds among the tidal eddies of the coast. They are generally rare and only locally abundant in any case.

Owing to their rarity many of the species of Stauromedusae are imperfectly described, and it is probable that some of them should be reduced. Kassianow, 1901, has studied the nervous system of Liicernana, Haliclystus, and Craterlophus, and the results of his studies are here reviewed in the discussion of the genus Lucernaria, wherein I have also reviewed the brief observations of Fol and of Kowalevsky, 1884, upon the early stages of the develop- ment of Lucernaria.

The sessile Stauromedusae display no rhythmical pulsation in their bells, but no studies have been made to discover whether the larvae at any stage possess this power. Hornell, 1893, and Browne, 1896, have studied the variations of Haliclystus octoradiatus. The results of their studies are referred to in the description of this species.

According to A. Meyer, 1865, the Lucernaridae have great regenerative power. The bell may reproduce a new stalk and parts of the medusa may regenerate the whole (see genus Haliclystus}. Kassianow, 1901 (Zeit. fur wissen. Zool., Bd. 69, p. 371), reports upon some- what similar experiments upon Craterlophus.

The relationship which may exist between the Stauromedusae and the Carybdeidae is discussed in the introduction to this volume.

Genera TESSERA, TESSERANTHA, and TESSERARIA Haeckel, 1880.

Tessera, Tesserantha, HAECKEL, 1880, Syst. der Medusen, pp. 373-375; 1 88 1, Deep-Sea Medusae Challenger Exped., vol. 4, p. 49. Tesseraria, HAECKEL, iSSo, Syst. der Medusen, p. 633.

Haeckel describes 4 specimens of these medusae from preserved material, and is the only naturalist who has seen them. They are said to differ from other Stauromedusae in their solid, non-knobbed tentacles, and in their being free-swimming, non-attached forms.

Haeckel states that these medusae have a simple, uncleft, umbrella margin, no marginal anchors, but 8 to 16 simple, perradial, interradial, and adradial tentacles. The broad marginal ring-muscle of the subumbrella is entire, not divided into 8 isolated sectors. Centripetal to the ring-muscle there is a system of radial-muscles. The medusae are pelagic and have no stalk of attachment, although a hollow apical projection is found at the aboral pole of the bell. The tentacles are solid and do not terminate in nematocyst-knobs.

The stomach gives rise to 4 wide, perradial, gastric pouches which are possibly divided one from another in the 4 interradii by 4 short, narrow septa. These septa extend centniugally from the 4 gonads, but are so short that they do not reach the bell-margin, and thus there is a wide, marginal, gastral ring-sinus. There are 4 interradial, horse-shoe-shaped gonads with their free ends pointing outward. 4 simple lips and 4 interradial areas of gastric filaments in the stomach.

According to Haeckel these 3 genera are distinguished as follows:

Tessera, with 8 tentacles, 4 perradial and 4 interradial. Bell 4 to 8 mm. wide.

Tesseranlha, with 16 tentacles, 4 perradial, and 4 interradial, and 8 adradial. Bell 6 mm. wide.

Tesseraria, with 32 tentacles. Bell 10 mm. wide.

In all respects these medusae resemble one another so closely that I am lead to suspect that they may prove to be but stages in the growth of one and the same medusa. It will be observed that the larger medusae have the greater number of tentacles.

The following is a brief diagnosis of the characters of these medusae, according to Haeckel:

Tessera princeps Haeckel, 1880 (Syst. der Medusen, p. 347, taf. 21, fign. 1-6), is 5 mm.

high and 4 mm. wide, with a pyriform bell and hollow apex. There are 4 perradial tentacles

about as long as the bell height, and 4 shorter (undeveloped ?) interradial tentacles. There

STAUROMEDUS.E — TESSERA, TKSSERANTHA, TESSKH.MM \, m T\sTIJUM.

523

are only 4 simple, interradial, gastric cirri, one in each interradius of the central stomach above (centripetal to) the 4 horse-shoe-shaped gonads. A single specimen was found hy the Chal- lenger southeast of Kerguelen Island, Antarctic Ocean, on February 19, 1874.

Tessera typus Haeckel, 1880 (//<;,/., p. 638), bell 8 mm. wide, 12 mm. high, pyramidal, 4-sided, elongate. 8 tentacles, 4 perradial and 4 interradial. of t-c|ual lengths, each nearly twice as long as the bell-diameter. 6 to 8 gastric filaments in each interradius. 4 hoise-shoe-shaped gonads in proximal half of subumbrella. A single specimen from the Indian Ocean, south of Madagascar.

Tesseranilm emuiettfns Haeckel, 1880 (Syst. der Medusen. p. 373; iSSi. Deep-sea Medusae CJuillrtiyer Expedition, Zool., vol. 4, p. 50, plate 15, tigs. I to 8 1 differs from "Tessera pritiifps" in being larger and in Inning id tentacles and numerous gastric cirri. The medusa is 9 mm. high and 6 mm. wide. The tentacles are perradial, interradial, and adra- dial, the largest being the first named, and the last quite short and apparently immature. There is an ectodeimal pigment spot on the exumbrella side of the base of the 8 perradial and interradial tentacles. A ridge of nettle cells extends toward the apex of the bell from the base of each tentacle. These pigment spots and ridges are not seen in Tessera prince ps. The numerous gastric cirri are arranged on both sides of the 4 interradial partial septa or taeniola of the central stomach. The 4 interradial pits of the subumbrella are deeper than in Tessera. Altogether all of the differences between Tessera and Tesserantha are such as one would expect to find in one and the same medusa in advancing stages of growth.

Tesserantha ennneetens was found by the Challenger near the island of Juan Fernandez, South Pacific, at a depth of 2,160 fathoms. It is elaborately described by Haeckel, 1881.

Tesserana scyphomeda Haeckel, 1880 (IbtJ., p. 638), has a goblet-shaped bell, 10 mm. wide, 15 mm. high. 32 tentacles equal each to each and not quite as long as the bell-diameter. 4 simple rows of gastric cirri. 4 horse-shoe-shaped gonads.

Found in Bass Straits between Australia and Tasmania. One specimen in GodefTroy Museum.

Genus DEPASTRUM Gosse, 1858. Depaitrum, GOSSE, 1858, Annals and Ma.?. Xat. Hist., vol. 1, ser. 3,

r-4'9-

Dcpastrum + Dtpastrtlla, HAF.CKEL, 1880, Syst. dcr Medusen, pp.

376, 378. Depastrum, DIXON, G. Y. and A. !•'.. iS.|-,, Pror. Kov. Dublin Soc.,

\ 1. !\, p. iSo. — B> \r MM\ i. i $94, Trans. Liverpool Bfol. Soc.,

vol. 7, p. 154.— MAASj nio(>, K.iuna Arctica, Bd. 4, p. 500. CarJuellii, ALIVHN, 1860, Rrport British Association, p. 143. — Clark,

1863, Boston Journal Nat. Hist., vol. 7, p. 546.

The type species is Depastrum cyathiforfne of the northern coasts of Europe, first described by M. Sars, 1846, as Lucernana cyathiforme. Gosse, 1858, established for it the genus Depastrum.

GENERIC CHARACTERS.

Stauromedusnc with 16 clusters of tentacles, 4 perradial, 4 interradial, and 8 adradial, arranged in one or in several rows around the bell-margin. Tentacles are all similar each to each, and are hol- low, and terminate each in a nematocyst-knob. There may be one or more tentacles in each per- radius and interradius. No marginal anchors. With divided stomach-pouches as in the Cleistocarpidae. An unbroken marginal, subumbrella ring-muscle. 4 small, interradial partial septa in the central stomach, leaving a wide, marginal ring-sinus. 4 interradial horse-shoe-shaped gonads with their convexities inward

FIG. 333. — Tesserantha connectcns, after Haeckrl in Deep sea Medusa.1 of Chnllengrr Expedition.

524 MEDUSAE OF THE WORLD.

and free ends directed centripetally. A 4-sided throat-tube. An aboral stalk serving for attachment. The adradial lobes are reduced to 8 barely discernible sinuosities.

Depastrella Haeckel, with 1 6 clusters of marginal tentacles arranged in a single row, is probably only the young of Depastrum. Depastrella appears to be intermediate between the Tesseranthinae and the Lucernarinae.

Depastrum cyathiforme Gosse.

Luccrnaria cyaihiformt, SARS, M., 1846, Fauna Littoral, Noweg., fasc. I, p. 26, taf. 3, fign. 8-13.

Depastrum cyathiforme, GOSSE, 1858, Annal. and Mag. Nat. Hist., vol. i, p. 419; 1860, Ibid., vol. 5, p. 481, figs. 1-3.

Lucernaria cyathiformis, KEFERSTEIN, 1862, Zeit. fur wissen. Zool., Bd 12, p. 24.

Carduella cyalhiformis, ALLMAN, 1860, Trans. Microscop. Soc. London, 70!. 8, p. 125, plate 5. — Clark, 1863, Boston Journal Nat.

Hist., vol. 7, p. 546.

Calicinaria cyathijormis, MILNE-EDWARDS, 1860, Hist. Nat. der Corall., tome 3, p. 459, Paris. Dcpastrum cyathiforme, HAECKEL, 1880, Syst. der Medusen, p. 378 (literature); D. polare, p. 639, and Depaslrella carduella,

p. 376. Depastrum cyathiforme, DIXON, G. Y. and A. F., 1893, Proc. Roy. Dublin Soc., vol. 8, p. 180. — BEAUMONT, 1894, Trans. Liverpool

Bid. Soc., vol. 7, p. 254. — RUSSELL, 1904, Annals and Mag. Nat. Hist., ser. 7, vol. 13, p. 62, plate 5 (references to localities

on the British coast). — BROWNE, 1905, Proc. Roy. Soc. Edinburgh, vol. 25, p. 774 (found in the Firth of Clyde at Little

Cumbrae and near Keppel pier). — MAAS, 1906, Fauna Arctica, Bd. 4, p. 500.

Medusa urn-shaped, about 6 to 10 mm. wide and of somewhat greater height. Stalk about as long as bell-height, flexible, contractile, and with an irregularly expanded adhesive foot. Bell-margin sinuous, subumbrella deeply concave. 36 to 100 tentacles arranged in 4 perradial and 4 interradial clusters of I to 3 tentacles each, and 8 adradial clusters, each con- sisting of about 9 tentacles. The tentacles bear each a terminal knob in adult specimens and are hollow and not retractile. Mouth 4-sided, cruciform, with 4 perradial buttresses, between which there are 4 interradial funnel-like pits in the floor of the subumbrella extending down- ward into the tissue of the 4 septa. The 4 gonads form each an interradial horse-shoe, the outer points of which do not extend to the bell-margin.

According to Clark, 1863, the perradial stomach-pouches are each bridged across by a cross-partition or claustrum extending over from the sides of adjacent gonads. Thus the gonads are confined within the 4 axial chambers adjacent to the mouth and are separated by cross- partitions from the outer parts of the perradial pouches.

Color is dirty chocolate-brown, the stalk paler.

This form grows permanently attached to rocks between tide-limits and does not reattach itself if torn from its anchorage.

o

Northern coasts of Europe. It is generally rare, and is found only locally in such places as the Firth of Clyde, Orkney Islands, near Bergen, Norway, Weymouth, England, etc.

Beaumont, 1894, Maas, 1906, and other recent observers have come to the conclusion that Depastrella carduella Haeckel, 1880 (p. 376, taf. 21, fign. 5 to 12), is only the young or an undeveloped stage of the Depastrum cyathiforme. Also Depastrella allmani, from Handa Island and the Orkneys, and D. polare from Spitzbergen, described by Haeckel, 1880, p. 639, appear to me to be identical with D. cyathiforme.

When young the tentacles are arranged in a single row around the margin and there is but one tentacle in each perradius and interradius, but when older the perradial and inter- radial tentacles become three times as many, and the adradial ones increase so as to be arranged in several rows.

It appears to me to be fruitless to attempt to separate species upon the length of the peduncle, its winged or unwinged (contracted or expanded) condition, as has been done by Haeckel, and until more detailed studies of living specimens have proven the contrary to be the case we had better venture to assume that all of the so-called Depastrellas and other forms of the North Atlantic are synonymous with Depastrella cyathiforme.

Genus STENOSCYPHUS Kishinouye, 1902.

Stcnoscyphus, KISHINOUYE, 1902, Journal College Science, Tokyo, vol. 17, art. 7, p. 2, figs, i, 2. Stcnoscyphus (?) BROCH, 1907, Hydroiden und Medusen, Report Second Arctic Exped. Fram, No. \^, p. 9.

The type species is Stenoscyphus inabai Kishinouye, of Japan, which has 8 marginal anchors, 8 clusters of adradial tentacles, and a 4-chambered peduncle.

STU i.'fiMi-.iii s i-; STI NO8< 1 Nil S.

525

'.I M'RIC CHARACTFRS.

Stauromedusae with simple, undcft hell-margin without adradial lobes. With 8 (or 12 :i perradial and imei -radial nundinal "anchors," S (or I 2 ": I adradial clusters of knobbed tentacles. \\ith a ring-shaped, entire, coronal muscle. Stalk of attachment is 4 (or 6?) chambered. Stomach 4-chambered as in the Eleutherocarpidae. Gunads interradial or on both sides of the interradii.

Kishinouye would constitute for S. innlnn a ne\\ famil\-.the Sti IIHM \ phidx, which would he intermediate hei\\ei-n I laeckel's Tcssciid;i- and Lucernarida-. S. in<i/>,ii has a 4-chambered stalk and 8 separate, adradial gonads.

Broch, 1907, describes a medusa which may belong to tin- genus S/,n'ji,-\f>lius but which has 12(6 perradial and 6 interradial) marginal anchors and 12 adradial clusters of tentacles. 1 he mouth is 6-rayed instead of 4-rayed, as in X. inabai. A \ariation in the number of ra\s may be expected in these degenerate medusas and it seems inexpedient at present to sepa- rate the 6-rayed from the 4-rayed form.

Stenoscyphus inabai Kishinouye.

Dtfastrum inahai, KIMIIMH-VI, iSij-,. /,n. .1 ., vul. ?, p. 411..

Stenoscyphus inabai, KISHINOL vi, l')O2, Journal College Science, Tokyo, vol. 17, art. 7, p. 2, plate I, figs. I, 2.

About 25 mm. long, elongate, narrow, funnel-shaped, and quadratic in cross-section. Stalk with 4 interradial grooves. Exumbrella smooth; subumhrella beset with large, urn- shaped groups of nematocysts. The 8 principal tentacles are large, round, adhesi\e bodies (anchors). Secondary tentacles are short and knobbed, and arranged in 8 adradial clusieis of about 25 each. There are neither arms nor lobes to the subumbrella. The ring-like coronal muscle is well developed and entire. 4 long, deep, interradial, gastrogenital pits extendin". to the aboral end of the bell. 8 gonads, in form of 4 pairs of bands along the interradial muscles. Each gonad composed of 40 sacs in 2 rows.

Color dark brown flecked with white, anchors red, gonads bro\\n. Subumbrella pale-green, manubrium \cllowisli.

Kata-ura, Kii Province, and Misaki, Japan. In winter. Rare. Attached to Sargassum. The animal can detach itself from the Sar- ".assum "at will" and can crawl about, using its oral and aboral adhesive organs, thus effecting a locomo- tion resembling that of a leech. It can not swim by pulsations of the bell.

Stenoscyphus (?) hexaradiatus Broch.

Sttnoscvphus (?) hexaradiatus, BROCH, 1907, Hydroidcn uml Metlusen, Report Srn i in Arctic Eipcdition in the From, No. iz,

p. 9, taf. 2, fij-n.

Bell-shaped, with a cylindri- cal peduncle sonu -\\hat longer than height of bell. Bell about (' mm. wide, total height of stalk together with bell lomm. Throat- tube short, 6-sidcd. Peduncle pro- vided with 6 longitudinal muscles. 12 marginal anchors, 6 radial and 6 interradial. These are shaped verj much as ordinary tentacles, hut bent in the middle in a knee- like form, and each provided with an abaxial cushion. Tentacle-clusters arranged in 12 adradial groups, each composed of 7 to 10 tentacles which arise in several rows from the bell-margin. Among each cluster of suctorial tentacles there are one or more tentacles which resemble the marginal anchors. 6 horse-shoe-shaped, folded gonads with their con\e\ sides abaxial. The two wings of each horse-shoe do not extend to the circular muscle. Color

334

I'n.. -,-,4. — Stcnoseyphus inabia, after Kishimiuve, in Jcmr. College <•!

Tokyo, Japan. Fie. 335. — Steno.<c\phu! hexaradialut, after Broch, in Report of the Second

Nonvr^ian Arctic F.xpi-Jition in the "I''rarrt."

526 MEDUSAE OF THE WORLD.

This medusa is distinguished by its 6-rayed structure, whereas in S. inabai the peduncle is 4-sided and there are 8 adradial tentacle-clusters instead of 12 as in 5. hexaradiatus. It is possible, as Broch states, that S. hexaradiatus may be the type of a new genus, but we must await results of future studies before deciding this point. Unfortunately there is only one specimen, obtained by the From off Fosheims Peak, Arctic Ocean, on the second expedition.

A closely allied form from the Kurile Islands is described by Kishinouye, 1909, under the name Thaumatoscyphus Jistinctus. (See Appendix to this volume).

Genus LUCERNARIA 0. F. Miiller, 1776.

Lucernaria, MULLER, O.F., 1776, Prodromus Zoolog. Dan., p. 227. — SARS, 1846, Fauna littoral. Norveg., fasc. i,p.io. — AGASSIZ, L., 1861, Cont. Nat. Hist. U. S., vol. 4, p. 175.— CLARK,' H. J., 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 551. — AGASSIZ, A., 1865, North Amer. Acal., p. 62. — FOL, 1873, Jena. Zeit. fur Natunvissen., Bd-7, p. 487. — HAECKEL, l88c, Syst. derMeduscn,p. 389; 1 88 1, Deep-Sea Medusa;, Challenger Report, Zool.,vol. 4, p. 53. — HORN ELL, 1893, Natural Science, vol. 3, p. 208. — HURST, Ibid., p. 209.

Lucernosa, HAECKEL, 1881, Ibid., p. 62.

Lucernaria, KOWALEVSKY, 1884, Zool. Anzeiger, Bd. 7, p. 712. — KASSIANOW, 1901, Zeit. fur wissen. Zool., Bd. 69, p. 287, 1 1 fign., taf. 22-25. — HAAS, 1906, ArUtischen Medusen, Fauna Arctica. Bd. 4, Lfg. 3, p. 499.

Lucfrnaria+ Lucernosa, ANTIPA, 1892, Zoolog. Jahrb., Abth. Syst., Bd. 6, pp. 378, 391.

The type species of this genus is Lucernaria quadncorius from the northern Atlantic coast of Europe, Greenland, and America.

GENERIC CHARACTERS.

Stauromedusae with 4 simple perradial stomach-pouches as in Eleutherocarpidx. With- out marginal anchors or marginal papillae. Peduncle single-chambered with 4 separate taeniola or partial septa. 8 adradial lolies which bear tentacles.

Antipa, 1892, would restrict Lucernaria to include forms with gonads of simple structure, whereas "Lucernosa" he would institute to define forms having complex gonads made up of numerous more or less separated sacs set side by side in a series of follicular ridges. In this respect he follows the suggestion of Haeckel, 1881, p. 62.

In all young medusae of Lucernaria the gonads are simple, flat, leaf-like expansions in the entoderm of the subumbrella, and in many of the species they develop transverse ridges, and these may become so marked as to appear as deep foldings across the gonad, thus dividing it into a series of more or less sac-like corrugated pouches. This is, however, a relative matter and can not be safely used as a generic distinction; moreover, I think we should, if possible, avoid found- ing genera upon derails of internal anatomy requiring dissection to determine their condition.

Kassianow, 1901, finds that in Lucernaria, Craterlophus, and Halicl\stits there is a plexus of bipolar ganglion cells in the ectoderm of the exumbrella. These ganglion cells have each two nuclei. There is a motor center at the point of each arm, and the nervous epithelium spreads out from the bases of the tentacles. The perradial and interradial anchors are not motor centers as one would expect them to be were they derived from rhopalia.

The early development of Lucernaria has been studied by Kowalevsky, 1884 (Zool. Anzeiger, Jahrg. 7, p. 712), who found that the eggs and sperm were discharged in the Bay of Sebastopol near evening in August. The segmentation is total and equal, and the entoderm is apparently formed by delamination. A single, central, entoderm cell was seen, however, with a slender prolongation extending from between the ectoderm cells, and thus it is possible that the entoderm may originate from one of the ectoderm cells which withdraws into the interior. The larva elongates, the entoderm becoming a single linear row of cells, and the ectoderm becoming very thin at the ends. The ectoderm is not ciliated, but the larva creeps about. On the fourth day the larvae attach themselves and become flat and rounded, and the entoderm forms a mass instead of a single layer, as previously. The larvae then encyst themselves in a hard, secreted covering, within which they remain for about two weeks; after escaping they became lost to observation. Fol, 1873, found also that in Lucernaria the seg- mentation is complete and results in the formation of a single-layered blastosphere, which elongates, becomes ciliated and 2-layered. After this it becomes attached. 8 small, tentacle- like, marginal bodies, 4 perradial and 4 interradial, appear, but soon degenerate and disappear. Thus apparently Lucernaria is descended from a Haliclystus-like ancestor. Hornell, 1893, states that 8 marginal anchors are found in the young medusa, but disappear in the adult.

STAUROMEDUS/E — LUCERXAK1 \.

527

Synopsis of the Species of Lucernaria.

	L. quadricornis Mullcr.	L. pvramidalis Haeckel.	L. waiter! Antipa.	L. kukenthali Antipa.	L. haeckeli Antipa.
Width of bell in mm.	50 to 60	40 to 50	55 to 60	55 to 60	*7
Height of bell without peduncle in mm.	25 to 30	5°±	70 ±	8o±	45 to 5°
Length of peduncle in	25 to 40	40 to 50	8o±	70 ±	'5
mm.
Angular distance between arms.	The 4 perradial notches twice as wide and deep as the intcrradial.	As in L. quadri- cornis.	As in L. quadri- cornis.	The 4 pt-rr.iji.il nottllr , 1 ! wide and deep as the 4 intcrradial.	The 4 perradial notches only little whler and deeper than the 4 inter- radial
Number of tentacles on each arm.	IOO to 120	1 1O to 140	700 to 750	800 to 850	80 to 90
Form and position of gonads.	8 from beginning of peduncle to ends of arms.	& from base of peduncle only to crotch of each arm.	8 wide lancet-shaped extending lo ends of 8 arms.	8 small, lancet- shaped, cross- • hands reaching to ends of 8 arms.	8 very wide, over- lapping; extending not quite to bases of 8 arms.
Color.	Very variable.	>	Light brown.	>	>
Where found.	North Atlantic coasts of Europe and America.	Labrador coast. Is this not L. quadricornus contracted	East Spitzbergen, Arctic Ocean.	East Spitzbergen, \i> lie Ocean.	East Spitzbergen, An tic Ocean.
		through preser- vation in alcohol ?
	L. infundibulum Hacckel.	L. campanulata Lamouroux.	L. bathvphiU Haeckel.	L. australis Vanhoffen
				(immature).
Width of bell in mm.	M	20 to JO	50 to 60	9
Height of bell without peduncle in mm.	'3	20 to 25	55 to 7o	10
Length of peduncle in	7	10 to 15	5 to 10	Absent or undeveloped.
mm.
Angular distance be- tween arms.	As in L. haeckeli.	45° apart. Similar each to each.	As in L. kiikenthali.	As in L. quadricornis.
Number of tentacles on each arm.	60 to So	30 to 40	So to 1:0	25 to 30
Form and position of gonads.	From middle of pedun- cle to bases of arms.	KroFFl point of jurutiirr hetween bell and peduncle to tips of 8 arms.	Broad and short. Neither •11^ to base of |v,him Ir nor ends of arms. K.tch gon.id has 200 sac-lilce fo],!-	Not developed.
			ings.
Color.	?	Vrrv v .triable.	>	>
Where found.	Spitzbergen, Arctic ( In'. in.	Hlack St-a and Medi- terranean to English coast. New Zea- land ( ?)	Between Faroe and Mn-'l.ind Islands, North Atlantic. From a depth of 540 fathoms.	Gauss Station, Ant- arctic Continent. l-'roFii depth of 192 fathoms. Novein 1902.

Lucernaria quadricornis 0. F. Muller.

Luctrnaria quadricornii, Mi;t LKR, O. F., 1776, Prodrorn. Zoo]. Dan., p. 227; 1788, Zoo). Dan., vol. i, p. 51, plate 39, figs. 1-6 — I. \MARCK, 1816, Syst. Anim. sans Vert., torn. 2, p. 354. — CuvitR, 1817, Ki'gne Anim.il. torn. 4, p.1 53. — SARS, M., 1829, Bidragtil Sodyrencs Natur., fasc. 1, p. 43, tab. 4, figs. 14-18; 1846, Fauna littoral. Norvei;., !•! « • i. p. 20. pl.ite ;, rigs. 1-7. — STIMPSON, 1853, Smithsonian Cont. to Knowledge, Marine Invert. Grand Manan, p. 8.— CARDS, 1857, Icon.. Zootom, taf. 4, fign. i, 2. — CLARK, H. J., 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 552, (good list of literature). — AGASSIZ, A. iSis, North Ainer. Acal., p. 62. — HAECEEL, 1880, Syst. der M 111 : . p, vi~ Ki F i HM us, 1863, Zeit. fur wisscn . Z<><il .. Bd. 12, p. 20. — TASCHF.NBF.RG, 1877, Halle, Zeit. ges. Naturw., Bd. 49, p. 82, taf. 2, fig. 2.

Disk about 50 to 60 mm. in diameter and, together with the peduncle, 50 to 70 mm. in height. The bell is of the shape of a 4-sided funnel and about twice as wide as high. Peduncle

f)l'S

MEDUSAE OF THE WORLD.

somewhat longer than the hell-height and with 4 longitudinal, mterradial strands of muscle- fibers. Bell-margin divided by 8 clefts or notches, the 4 perradial ones being about twice as wide and deep as the 4 interradial; thus the 8 arms are brought quite close together in 4 separate pairs. Each arm bears 100 to 120 tentacles. The stomach gives rise to 4 wide, perradial pouches, which are lined on their edges by the 8 gonads.

Color variable, being either gray, green, yellow-brown, red-brown, or very dark brown.

Found on the northern coasts of Europe, on the Greenland coast, and on the coast of America, north of Cape Cod. It has never been taken south of Massachusetts Bay. Very rare on American coast.

Complete descriptions and good figures of this medusa have been given by Sars, 1846; Carus, 1857; and Taschenberg, 1877.

Lucernaria "pyramidalis" Haeckel=L. quadricornis (?) Luctrnaria pyramidalis, HAECKEL, 1880, Syst. der Medusen, p. 391, taf. 22, 10 fign.

Bell 4-sided and pyramidal, about 40 to 50 mm. wide and (with the style) 90 to 100 mm. high. The 8 arms grouped in 4 pairs, the 4 perradial notches of the bell-margin being twice as wide and deep as the 4 interradial. Each arm bears a large cluster of 130 to 140 tentacles.

FIG. 336. — Lucernaria "pyramidalis," after Haeckel, in Das System der Medusen.

Peduncle about 0.25 to 0.33 longer than bell-height. 4 short, blunt taeniola at its free distal end and a sharply marked pyloric stricture at its proximal end at base of bell. 4 linear, inter- radial strands of muscle-fibers traverse the length of the peduncle. Mouth cruciform, with 4 short, folded lips. The gonads are 8 blindly ending, transversely folded bands, grouped into 4 interradial pairs. They begin on the floor of the subumbrella at a short distance above the pyloric stricture and extend only to the crotch of the bell-arms. They diverge centnf-

STAUROMEDUS^E — LUCERNAIUA. .">'_".)

ugally outward, and the components of each pair are separated one from another by the 4 interradial septa. The gastric filaments in the regions of the gonads are small but very numerous.

This form is found on the Labrador coast. A good description oi it is given by Haeckel, 1880. It is certainly closely related to, if not identical with /,. quaJricornis, but Haeckel states that the peduncle is separated from the bell by a pyloric stricture, or ring-furrow, which is not the case in L. ijuiidncornis. Haeckel studied only preserved specimens and I strongly sus- pect that this so-called pvloric constriction may have been caused by unnatural contraction.

Lucernaria walteri Antipa. Lucernosa walteri, ANTIPA, 1892, Zoolog. Jahrb., Abth. Syst., Bd. 6, p. 379, taf. 17, fign. 1-9.

150 to 160 mm. high and 55 to 60 mm. across the bell. Bell goblet-shaped; stalk round, single-chambered, somewhat higher than the bell. Stalk with 4 well-developed, linear, inter- radial, longitudinal muscles. 8 arms arranged in pairs with the 4 perradial concavities between the arms twice as wide at the 4 interradial notches of the margin. Each arm with a terminal, ball-like cluster of 700 to 750 short, knobbed tentacles. 8 wide, lancet-shaped, adradial gonads, extending to ends of the 8 arms; they are folded, band-like, and he in the subumbrella wall of the perradial stomach-pouches. The cavity of the stalk extends dncctly into that of the bell, without a pyloric stricture. Color light brown. East Spitzbergen, Arctic Ocean. This is one of the largest known Lucernarians. Special description given by Antipa.

Lucernaria kiikenthali Antipa. Luccrnosa kukcnthali, ANTIPA, 1892, Zoolog. Jahrb., Abth. Syst., Bd. 6, p. 386, taf. 18, fign. 10, 11.

More than 150 to 160 mm. high, 55 to 60 mm. wide across the bell. Bell goblet-shaped, somewhat higher than wide. Stalk not quite as long as the bell itself, with no constriction or other sharp distinction between stalk and bell. Stalk round, single-chambered, with 4 well-developed, linear, longitudinal muscles. 8 arms arranged in pairs. The 4 perradial notches of the bell-margin are 3 times as wide and 3 times as deep as are the interradial. Each arm has a terminal, ball-like cluster of 800 to 850 short, knobbed tentacles. Gonads are 8 small, lancet-shaped, cross-folded bands extending to ends of the 8 arms. Color (?) East Spitzbergen, Arctic Ocean. Described in detail by Antipa, 1892. I am inclined to suspect that this is only a variety of, if not identical with, Lucernaria walteri. It appears to be dis- tinguished only by its narrow lanceolate gonads and slightly wider perradial notches.

Lucernaria haeckeli Antipa. Lucernosa haeckeli, ANTIPA, 1891, Zoolog. Jahrb., Abth. Syst., Bd. 6, p. 388, taf. 18, fign. 11-14.

60 to 65 mm. high and 27 mm. wide at widest part, which is below bell-margin. Bell oval, goblet-shaped, widest near middle. Stalk conical, wide, and hardly one-third as Ion.; as bell. Stalk single-chambered with 4 interradial, longitudinal muscles. 8 short arms arranged in pairs. The 4 perradial notches of the margin only a little wider and deeper than the 4 interradial notches. Each arm terminates in a hall-like cluster of 80 to 90 knobbed tentacles. 8 very wide gonads, so wide that they overlap one another. The gonads extend not quite to bases of arms, and quite fill the lower pans of the radial chambers of bell.

This species is distinguished from /,. l>tit/i\[>ltila by its short bell-stalk and the position and shape of its gonads. Color (?) East Spitzbergen, Arctic Ocean.

Lucernaria infundibulum Haeckel. Lufernaria infundibulum, HAFCKF.L, 1880, Syst. iler Medusen, pp. 391, 385.

Bell funnel-shaped, Hat, not quite twice as wide as high, 24 mm. wide. Peduncle some- what less than 10 mm. long, 4-sided, pyramidal, and single-chambered. The medusa is distinguished by having 4 hollow, interradial txniolx each with a funnel-like, central cavity extending to lower end of peduncle, recalling the condition seen in the aboral end of bell in Periphylla. Each hollow septum bears along the entire length of its side walls a pair of well- developed longitudinal muscles and 2 rows of gastric filaments. The 8 umbrella-arms are arranged in 4 pairs, the 4 perradial notches being wider than the 4 interradial. Each arm has

* — *

530

MEDUSAE OF THE WORLD.

60 to 80 tentacles. 8 gonads extending from middle of peduncle to base of arm. Found at Spitzbergen. Described by Haeckel from a preserved specimen.

Lucernaria campanulata Lamouroux.

Lucernaria campanulata, LAMOUROUX, 1815, Mem. du Museum Hist. Nat., tome 2, p. 472, planche i6,figs. 1-7. — KEFERSTEIN, 1862, Zeit. fiir wissen.Zool., Bd. 12, p. 23, taf. I, fig. 4. — HAECKEL, 1880, Syst. der Meduscn, p. 392 (list of literature). — HUTTON, 1880, Trans. New Zealand Institute, vol. 12, p. 275. — CLAUS, 1883, Untersuch. u'ber Organisation und Entwick. der Meduscn, p. 35. — GRAEFFE, 1884, Arbeit. Zool. Inst. Wien., Bd. 5, p. 344. — HORNELL, 1893, Nat. Sci., London, vol. 3, p. 208. — BEAUMONT, 1900, Proc. Roy. Irish Acad. Dublin, Ser. 3, vol. 5, p. 8n. — Kassianow, 1901, Zeit. fiir wissen. Zool., Bd. 69, p. 370, fig. ii.

Lucernaria convolvulus, JOHNSTON, 1835, London, Mag. Nat. Hist., vol. 8, p. 59, fig. 3.

Lucernaria, KOWALEVSKY, 1884, Zool. Anzeiger, Jahrg. 7, p. 712 (embryology).

This medusa is at once recognized by its symmetrically octagonal disk with its 8 arms 45° apart and with equally developed notches between them. There are no longitudinal muscles in the 4 interradial longitudinal ridges of the peduncle. The medusa is 20 1030 mm. wide and 30 to 40 mm. high, including the peduncle. Color very variable, being yellowish, red, brownish, etc. Found along European coasts from the Black Sea and Mediterranean 10 southern England, Ireland, and Wales. Graeffe states that it is found only locally at Trieste, Adriatic Sea, in May and June, becoming mature at the end of the latter month. Hutton records it from Brighton near Dunedin, New Zealand, but he gives no description.

For an account of Kowalevsky's observations upon the early stages of the larva see genus Lucernaria.

Hornell, 1893 (Nat. Sci., vol. 3, p. 208), states that 8 marginal anchors are found in the young medusa, but they soon disappear and are not found in the adult. This leads one to con- clude that Lucernaria is derived directly from Haliclystus. Indeed Horst, 1893, finds that the variations in number and development of the marginal anchors is so great that he is inclined to consider Lucernaria to be identical with Hal- iclystus. Kassianow, 1901, records the capture of an abnormal specimen having 2 medusa bells arising from one stalk.

Lucernaria bathyphila Haeckel.

Lucernaria bathyphila, HAECKEL, 1880, Syst. der Medusen, p. 640; 1881, Report Deep-Sea Medusa; Challenger Expedition, Zool., vol. 4, p. 54, plates 16, 17, 21 figs.

Lucernosa bathyphila, ANTIPA, 1892, Zoolog. Jahrb., Abth. Syst., Bd. 6, p. 379.

FIG. 337. — Lucernaria bathyphila, after Haeckel, in Deep-sea Medusa Challenger Expedition.

For description, see synopsis of the species of Lucernaria. Haeckel, 1 88 1, gives a very detailed and fully illustrated description of this species.

Lucernaria australis Vanhoffen. Lucernaria australis, VANHOFFEN, 1908, Deutsche Su'dpolar-Exped., 1901 to 1903, Bd. Id, Zool. 2, p. 32, fign. I, 2.

Described by Vanhoffen from an immature specimen which had neither gonads nor peduncle.

Bell 10 mm. high, 9 mm. wide, thimble-shaped, with sloping sides. No basal stalk, but with a weakly developed ring-furrow at aboral end of bell, and an indication of the beginning of a single-chambeie5<1pe.duncle. 8 short arms, 2 to 2.5 mm. long, grouped in pairs somewhat closer in the interradii than in the perradii, and with the perradial concavities of margin deeper than the interradial. 25 to 30 short tentacles, with small terminal knobs on each arm. There were 7 very small, tentacle-like marginal bodies somewhat asymmetrically placed near the 4 perradial and 3 of the interradial points of the bell-margin. It is therefore possible that this medusa may be a young Haliclystus, but if the marginal bodies degenerate it is a Lucernaria, for such a course of development is known according to Hornell, 1893, in the European species of Lucernaria. The 4 perradial lips of the cruciform mouth are folded and are at about half the distance between the depth of bell-cavity and margin.

STAUROMEDUS^: — KISHINOUV 1. A , II \ I.ICI.VSTUS. 531

Wide ring muscle at margin of subumbrella and 8 strands of radial-muscles extending outward to the tentacles. These radial strands are one-third wider than the ring muscle. They inclose 4 narrow, triangular areas in the interradii and 4 wider, rectangular spaces in the perradii. These subumbrclla areas between the muscle strands exhibit many large nettle- cells. There are about 12 simple, unhranched, gastric filaments in each ot the 8 rows. Found at Gauss Station. Kaiser \Vilhelm II Land, Antarctic Continent, at a depth of 192 fathoms, in November, 1902.

Genus KISHINOUYEA, nom. nov.

SchizoJiscus, preoccupied by Kittl, 1891.

Schizodiscus, Ki-iir.mit, 11)02, Jour. College Sci., Tokyo, vol. 17, art. 7, p. 5.

The type species is K , nagatfnsis of Japan, first described hv Oka under the name Lnccr- iniiiii naatitcnsis.

GENERIC CHARACTERS.

Stauromedusae with 4-chambered stomach as in the Eleutherocarpidae, and without adhe- sive anchors. Umbrella deeply notched, with 8 adradial lobes. 8 adradial clusters of knobbed tentacles. Peduncle 4-chambered without muscle-fibers in the txniola. Gonads 8 adradial hands of laterally oblong sacs.

This genus is very closely allied to Lucc-rnaria and is distinguished only by its 4-cbambered aboral stalk. In young medusa;, however, it is single-chambered, as in Lucernana, but the 4 interradial septa, or txniola, unite near the pvloric region as growth proceeds, and thus the peduncle comes to have 4 perradial, separate chambers.

Kishinouyea nagatensis.

Lucernaria nagaiensis, OKA, 1897, Zool. Mag. Tokyo, vol. 9, p. 67, plate i. Also; Annul, /mil. J.ippon. Tokyo, vol. 1, p. 141,

4 fiSs- Schifttdisctti nagatensis, KIMIIMII j\t, 1902, Journ. Science College, Tokyo, vol. 17, art. 7, p. 6, plate i, figs. 3-6.

The 8 adradial lobes are united in pairs, so that the 4 perradial notches are about twice

as deep as the 4 interradial. These 8 adradial lobes are bent at right angles to the oral side. The disk has the shape ot a Greek cross. Peduncle 4-chambered in adult. Well-developed, interradial, longi- tudinal muscles in the subumbrella. Marginal muscle divided into 8 U- shaped pieces. No primary tenta- cles. Adradial tentacles short, adhe-

I'l.;. 538. Kishinouyea naKaicn,i,, afi.-r Kishinouye, sive, in clusters of 5. Gastral tila-

in Jour. Col. of Science, Tokyo. • i i ,- • '

ments branched, tew in number.

Gonads, 8 broad, adradial bands ot laterally oblong sacs. Color variable, matching its surroundings. Japan.

Genus HALICLYSTTJS Clark, 1863.

Haliclyslus, CLARK, 1863, Journ. Boston Soc. N'.it. Hi t., vol. 7, p. 559; 1878, Smithsonian Contributions to Knowledge, Article 2, Part. 2. — AGABSIZ, A., 1865, North Amer. Acal., p. 63. — HAECKEL, 1880, Syst.dcr Medusen, p. 387. — KISIIINOUYE,

1889, Proc. U. S. National Museum, v»l. >:.]>]'. i:;. i:-i. M VAS, 1904, Re'sult Camp. Sci. Prim > .;. M n.tco, fasc. 28, p. 43; 1906, Fauna Arctica, Bd. 4, Lfg. 3, p. 499. — Gross, 1900, Jena. Zeit. fur Natunvissen, Bd. 33, p. 614 (anatomy). Lucernaria, BfRt.u, 1888, Vidcnsk. Meddtl. Xaturhist. l'<ir. Kjobenliavn, p. 214 (embryology).

The type species of this genus is H. auricula from the Atlantic coasts of Europe and of New England, United States.

GENERIC CHARACTERS.

Stauromedusae similar to Lucernaria but with 8 perradial and interradial marginal anchors, and with a 4-chambered, aboral peduncle. The embryology has been studied by Bergh, 1888, and is similar to that of Lucernaria, excepting that in Lucernaria the 8 anchors become lost as growth proceeds.

532

MEDUSAE OF THE WORLD.

The regeneration of Haltclystus has been studied by A. Meyer, 1865 (40 ste Versamml. deutsch. Naturforscher Aerzte, Hannover, p. 217), who gives a brief account of his experiments. It appears that the medusa possesses considerable regenerative capacity. The style is regen- erated if it be removed, and if only the lower end of the style be cut off the medusa usually regenerates a new aboral end; but occasionally a bell is regenerated, thus giving an animal with 2 bells. Somewhat similar results were attained by Kassianow, 1901, on Craterlophus.

Characteristics of the So-called Species of Haliclystus.

	H. octoradiatus.	H. salpinx.	H. stejnegeri.	H. auricula.	H. antarcticus.	H. kerguelensis.
Umbrella.	Conical, surface	Pyramidal,	Conical, surface	Pyramidal,	Flat, twice as wide	As in H. antarc-
	flat, 2 to 3 times	octangular,	flat, a little	octangular,	as high, conical.	ticus.
	as broad as high.	much broader	broader than	almost as broad
		than high.	high.	as high.
Peduncle.	Cylindrical, al-	Quadrangular,	About half as long	Almost as long as	4-sided, prismatic,	Twice as high as
	most as long as	prismatic,	as height of um-	height of um-	half to two-	umbrella.
	height of um-	considerably	brella, with 4	brella, with 4	thirds as long as	Prismatic,
	brella; no inter-	longer than	interradial longi-	deep longitudi-	height of um-	4-sided.
	radial longitudi-	height of um-	tudinal grooves.	nal grooves.	brella. With 4
	nal grooves.	brella.			longitudinal
					grooves (con-
					tracted ?).
Eight arms.	45° apart. Each	45° apart.	45° apart. Each	United in pairs.	45° apart and	As in H. ant-
	arm with 30 to 60	Each arm with	arm with 70 to	Each arm with	similar each to	arcticus, but
	tentacles.	60 to 70 tenta-	100 tentacles.	100 to 120 tenta-	each. Each arm	with not more
		cles.		cles. Interradial	with more than	than 50 tenta-
				clefts only half	100 tentacles.	cles on each
				or two-thirds as		arm.
				wide as pcrradial.
Eight	Large, egg-shapec	Very large, as	Large, egg-shaped,	Largr, shaped like	Large, biscuit-	Small, oval, only
marginal	or nearly club-	long as arms,	half as long as	corTee-beans,	shaped, about as	one-third as
anchors.	shaped, one-	obliquely	breadth of	as long as	long as width of	wide as width
	fourth as long as	trumpet-	peduncle.	breadth of	peduncle.	of peduncle.
	breadth of	shaped.		peduncle.
	peduncle.
Gonads.	In each gonad 20	In eacli gonad	In each gonad 100	In each gonad loo	8 gonads, widely	8 widely
	to 30 large sacs	40 to 50 sacs	to 150 sacs, 6 to	to 150 sacs in 6	separated one	separated,
	in 2 longitudinal,	in 4 longitudi-	8 sacs abreast in	to 8 radial rows.	from another,	broad, lancet-
	alternate rows.	nal rows.	the broadest		100 to 150 sacs	shaped gonads.
			part.		in 6 to 8 radial
					rows in each
					gonad.
Where	North Atlantic.	Coast of Maine,	Boring Island,	North Atlantic.	Island of South	Kerguelen
found •		United States.	Commander	Coasts of Europe	Georgia, Ant-	Island, Ant-
			Islands, North	and America.	arctic Ocean.	arctic Ocean
			Pacific.

Haliclystus auricula Clark.

Lucertiaria auricula, RATHKE, 1806, Miiller's Zool. Dan., Bd. 4, p. 35 (exclus. syHow),

Ifaliclystus auricula, CLARK, H. J., 1863, Jour. Boston Soc. Nat. Hist., vol. 7, p. 559. — AGASSIZ,A., 1861;, North Amer.Acal., p. 63, figs. 88-90. — CLARK, S. F., 1876, Exploration of Alaska, vol. I, p. 235. — CLARK, H. J., 1878, Smithsonian Contributions to Knowledge, pp. 1-130, plates 1-9, 145 figs. — HAECKEL, 1879, Syst. der Medusen, p. 389. — SCHLATER, 1891, Zeit. wiss. Zool., Bd. 52, p. 580; Revue Sci. Nat. St. Petersbourg, Anne. 2, p. 176 (sense-organs, structure of). — BEAUMONT, 1893, Trans. Liverpool Biol. Soc., vol. 7, p. 259; 1900, Proc. Roy. Irish Acad. Dublin, scr. 3, vol. 5, p. 806. — BIGELOW, H. B., 1909, Proc. U. S. National Museum, Washington, vol. 37, p. 316.

(?) Haliclystus tennis, KISHINOUYE, 1910, Journal College Sci., Tokyo, vol. 27, art. 9, p. 4, plate I, fig. 3.

Disk about 20 to 30 mm. wide and (with the style) 20 to 30 mm. high. Bell-margin 8-sided. The 4 interradial notches between the arms being only half to two-thirds as wide as the 4 perradial clefts. Each arm terminates in a large cluster of 100 to 120 tentacles. These tentacles are each about quarter as long as bell-diameter. They are hollow and terminate in a globular tip thickly covered with nemaiocysts. There are 8 large, perradial and interradial, marginal anchors (colletocystophores), which are coffee-bean-shaped and mounted, each one, upon a short cylindrical base. These organs are much larger than in the European H. octo- railiatns. The aboral peduncle, or stalk, is about as long as bell-height. It is cruciform in cross-section, there being 4 deep, interradial, longitudinal furrows beneath which are 4 well-'

STAUROMEDUS^E — HALICLYSTUS.

533

developed strands of longitudinal muscle-fibers. Alternating with these are 4 perradially situated, longitudinal chambers which communicate with the central stomach in the umbrella. There are 8 broad, adradial gonads, grouped into 4 interradial pairs. Each gonad is wide and triangular. These gonads begin a little above the point of junction of the stalk with the disk and extend to the ends of the 8 arms. Each gonad contains 100 to 150 out-tolded sacs arranged in 6 to 8 radiating, longitudinal rows. Gastric cirri numerous.

Fi<;.

i). Halielystus auricula, after Clark, in Smithsonian Contributions to Knowledge. The smaller figures arc of natural size and illustrate characteristic attitmlrs.

Color very variable, but each medusa is commonly of one color, parti-colored individuals being very rare. Individuals are cither blue, green, yellow, olive, orange, or very rarelv red, pink, or violet. Medusa; of brownish and purple hues are also common.

534 MEDUSA OF THE WORLD.

This species is found in Massachusetts Bay and off the northern coasts of Europe from England to Norway. Clark reports it from Norton Sound, Alaska, and Bigelow from Labra- dor and Newfoundland. It is only locally common on the New England coast.

It may be distinguished from H, octoradiatus by its more slender bell and stalk, its large marginal anchors, and the greater number and smaller size of the genital sacs upon the gonads. Kishinouye, 1910, records a form from Japan which resembles H. auricula excepting that each gonad consists of only two rows of saccules. He calls this medusa H. tennis.

Haliclystus octoradiatus Clark.

Lucernaria auricula, MONTAGU, 1808, Trans. Linn. Soc. London, vol. 9, p. 113, plate 7, fig. 5. — SARS, M., 1829, Bidragtil Sodyr. Naturhist., p. 34, taf. 4, fign. I to 13. — JOHNSTON, 1838, Hist. British Zoophytes, p. 229, fig. 35. — AGASSIZ, 1862, Cont. Nat. Hist. U. S., vol. 4, p. 176.

Lucernaria octoradiata, LAMARCK, 1816, Hist. anim. sans vert., torn. 2, p. 474. — STEENSTRUP, 1859, Vidensk. Meddel. Nat. Foren. Kjb'benhavn, p. 108. — SARS, M., 1860, Forhandl. Vid. Selsk. Christiania, p. 145. — KEFERSTEIN, 1863, Zeit. wissen. Zool., Bd. 12, p. 22, taf. i, fign. 1-3. — TASCHENBERG, 1877, Zeit. Ges. Naturw., Halle, p. 91, taf. 2, fig. 4. — BERGH, 1888, Vidensk. Meddel. Nat. For. Kjb'benhavn, p. 214, fign. 1-3.

Haliclystus octoradiatus, CLARK, H. J., 1863, Jour. Boston Soc. Nat. Hist., vol. 7, p. 565. — HAECKEL, 1880, Syst. der Medusen, p. 388. — LEVINSEN, 1893, Vid. Meddel. Nat. Foren. Kjb'benhavn, (5), Bd. 4, p. 146. — BROWNE, 1896, Quart. Journ. Mic. Sci., vol. 38, part. I, pp. 1-8, plate I, 22 figs. — HORNEI.I., 1893, Natural Science, London, vol. 3, p. 33 (abnormalities). — BROWNE, 1895, Quart. Journ. Micros. Sci., ser. 2, vol. 38, p. I, plate i (variations). — GROSS, 1900, Jena. Zeit. Naturw., Bd. 33, p. 611, taf. 23, 24 (anatomical). — BEAUMONT, 1900, Proc. Roy. Irish Acad., Dublin, ser. 3, vol. 5, p. 808. — MAAS, 1904, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 44. — WIETRZYKOWSKI, 1909, Comptes Rendus, Paris, tome 149, p. 746.

Disk 20 to 30 mm. wide and, with the stalk, 20 to 30 mm. high. Disk flat and about 2 to 3 times as broad as high. The 8 adradial arms are 45° apart, not grouped in 4 more or less approximated pairs, as in H. auricula. Arms very wide, concavities of bell-margin shallow. Each arm bears a terminal cluster of 30 to 60 tentacles, instead of 100 or more, as in H. auricula. The 8 perradial and interradial marginal anchors (colletocystophores) are egg-shaped, and about one-fourth as long as diameter of stalk. Stalk cylindrical, without longitudinal furrows, 4-chambered, and with 4 interradial, longitudinal strands of muscle- fibers. There are 8 separate gonads which do not extend quite to the end of the arms or to the aboral septa. Each gonad contains only 2 rows of alternately arranged, large, genital sacs.

Color quite variable, being either grayish-yellow, brownish-yellow, or grayish-brown.

Found on the North Atlantic coasts of Europe, on the Greenland coast, and at Spitzbergen.

The most complete descriptions of this species are given by Sars, 1829; Keferstein, 1863; Browne, 1895; and Gross, 1900. Its variations have been studied by Hornell, 1893, and by Browne, 1896. The abnormal forms are very irregular, symmetrical variations rarely appearing. The medusa is one of the most variable known. At Jersey, England, according to Hornell, 66 per cent of the specimens were abnormal in some respect; but at Plymouth, according to Browne, only 34 per cent were abnormal and the aberrations were quite different from those found at Jersey. We are unable to determine whether this difference is fostered by isolation or is due to the effect of local influences in the environments of Plymouth and Jersey. It may also be due to a difference in variative tendency in the medusae of the two places. The development of H. octoradiatus has been studied by Bergh, 1888. The egg is fertilized after being discharged into the water and then it retracts somewhat from the vitelline mem- brane. 2 polar bodies are found; the segmentation is total and equal, and there is no cleavage cavity. The entoderm appears to be formed by polar ingression of cells into the center of the solid morula which is at first spherical but afterwards it elongates into a rod-like form, which becomes so long and narrow that the entodermal cells come to be arranged one after another in a single row as in the planula of Soltnundella. The planula of H. octoradiata is not ciliated, however, but creeps about by means of worm-like movements. It then attaches itself by the anterior end as do other planulae of Scyphomedusae. At first the tentacles are not united into definite clusters but are distributed around the bell-margin, but 8 tentacles are more or less isolated and lie in the perradial and interradial radii. These form the marginal anchors.

The best description of the development of the planula is given by Wietrzykowski, 1909 (see Appendix to this Volume).

Bergh, 1888, describes an abnormal specimen of H. octoradiatus with a small bud arising from the side of its bell.

STAUROMEDUS^E — HALICLYSTUS. 535

Haliclystus salpinx Clark. Plate 56, figs. I to 4.

Haliclystus salpinx, CLARK, H. J., 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 563.— ACASSIZ, A., 1865, North Amcr. Acal.,

p. 64. — HAKC KEL, 1879, Syst. der Medusen, p. 388. ( >) Luccrnaria salpinx, GRAIFFF., 1884, Arbrit. Zool. Inst. \Vicn., Bd. 5, p. 344.

Disk 25 mm. wide and (with the stalk) 20 mm. high. The 8 adradial arms are 45° apart, and their ends are rounded. Each arm bears 60 to 70 very slender tentacles, the globose tips of which are smaller than in H. auricula. The 8 marginal anchors are as long as the arms, slender, and obliquely trumpet-shaped. The edge of the trumpet is considerably thickened except at a narrow space on the proximal side, by the development of adhesive cells. The center of this terminal expansion is occupied by a single tentacular remnant about as long as half the breadth of the trumpet. Aboral stalk relatively longer and more slender than in //. auriiiila, 4-sided in cross-section, with 4 longitudinal rows of interradial muscle-fibers. '1 he stalk is 4-chambered and about 12 mm. long. The 8 genital cugans are nor MI wiili-K separated as in H. auricula; their broader ends project only about half-way into the arms. The genital sacs of each gonad are arranged in 4 radiating rows, the marginal rows being shorter than the 2 middle rows. All of these sacs are of the same size and there are 40 to 45 of them in each row.

This species was obtained by Stimpson at Mount Desert Island, Maine. The best description of it is that of Clark, 1863. Our figures are drawn from specimens obtained upon eelgrass on the inner side of Ram Island near Manchester, Massachusetts, on September 7, 1905. Graeffe, 1884, appears to have lound this species at Trieste, Adriatic Sea, in June and July.

Haliclystus stejnegeri Kishinouye. Halidystus slejnegeri, KISHINOUYE, 1899, Proc. U. S. National Museum, vol. 22, p. 126, figs. 1-3.

Bell conical, funnel-shaped, 1.33 to 1.5 times as broad as high. 18 mm. wide. Peduncle nearly quadrate in cross-section and about half as long as umbrella; its 4 interradial, longi- tudinal grooves are formed by the attachment of the ta-niola. These septa meet at the longi- tudinal axis and divide the internal space of the peduncle into 4 perradial chambers which are continuous with the 4 perradial stomach-pouches. The surface of the exumbrella is smooth and the line of demarcation between the stalk and the umbrella is distinct, although there is no constriction at this point. There are a few small clusters of nematocysts at the radial sinuses of the umbrella margin. The radial muscle plates are, as in other species of Hali- clystus, developed in the perradii and interradii of the subumhrella. The margin of the umbrella displays 8 equally spaced, adradial arms, all of the same size. The 8 incisions are about as deep as the width of the arms themselves.

There are 8 large, egg-shaped, perradial and interradial "anchors," which are about half as long as diameter of peduncle; these are situated in the concavities of the clefts, alter- nating with the tips of the 8 adradial arm-lobes. There are 8 adradial clusters of knobbed tentacles, one at the end of each of the 8 arms. Each cluster contains 70 to 100 tentacles of various sizes.

Manubrium short and quadrangular, the lips reflected outward. The 8 rows of well- developed gastric filaments extend from the base of the throat-tube to the proximal ends of the 8 gonads. The 8 gonads are broad, leaf-shaped, tapering at both ends, and touch each other along their proximal halves, so that the surface of the subumbrella is almost entirely occupied by them. There are 100 to 150 round sacs in each gonad; these sacs are not arranged in rows and those nearest to the 4 principal radii are the largest. There are 6 to 8 sacs abreast at the broadest part of each gonad. Each gonad is turned over in the 4 principal radii and is continuous with the mesentery.

Preserved specimens are grayish or pale brown, semi-transparent, with a dark-brown or nearly black streak at bell-margin.

A number of specimens were found at Bering Island, one of the Commander Islands, North Pacific, in summer.

The species is well described and figured by Kishinouye (see text-figure 340).

536

MEDUSAE OF THE WORLD.

Haliclystus antarcticus Pfeffer.

Haliclystus antarcticus, PFEFFER, 1889, Mitthci]. Naturhist. Museum Hamburg, Jahrg. 6, p. 16.

Bell flat, 17 mm. wide to bases and 27.5 mm. wide to ends of arms. Height 11.5 mm. to subumbrella disk and I? mm. to ends of arms. The stalk is 8 mm. long, flexible, and when

-* O'

expanded it is about two-thirds as long as bell-height. It has 4 mterradial, longitudinal muscles and is 4-sided in cross-section, the longitudinal muscles being in the 4 flat or grooved sides. The attached end ot the stalk is swollen. There are 8 adradial arms 45° apart with the 8 clefts all of equal depth, and each arm has more than 100 tentacles; 8 large biscuit- shaped, marginal anchors about as long as width of stalk; 8 wide, lancet-shaped gonads, widely separated one from another and extending to ends of arms. The number of sacs in the gonads is not clearly defined in PfefFer's specimens, but there appear to be at least 100 to 150 in 6 to 8 longitudinal rows. Stalk single-chambered thus illustrating the close relation- ship between Haliclystus and Lucernana.

The medusa is a beautiful blue-violet in color, with lighter, somewhat reddish anchors and tentacles. Found at South Georgia, Antarctic Ocean.

Haliclystus kerguelensis VanhOffen. Haliclystus kerguelensis, VANHOFFEN, 1908, Deutsche Sudpolar-ExpeJition, 1901-1903, Bd. 10, Zool. 2, p. 31, taf. 2, fig. I.

Bell 27 mm. wide across the outstretched arms exclusive of the tentacles, and 10 mm. high. Arms 45° apart, the concavities between them all similar each to each as in H. antarc- ticus. Peduncle prismatic, 20 mm. long and 3 mm. wide. Not quite 50 tentacles in each adradial cluster. Marginal anchors only one-third as wide as the peduncle in its expanded state. 8 wide, lancet-shaped gonads.

^^

s^ 340.

FIG. 340. — Ha/iclystus stejnegeri, after Kishinouye, in Proc. U. S. Nat. Mus.

Fie. 341. — Hallclvstus kergurltnsh, after VanhuHen in Deutsch. SuJpolar Expedition.

peduncle sandy-brown with a play of green over the surface.

Bell and peduncle sandy-brown with a play of green over the surface. Gonads dark olive-brown and plainly visible through the walls of the lighter colored bell. Terminal knobs of the tentacles rose-red.

Found at Observatory Bay, Kerguelen Island, Antarctic Ocean; in July, growing on the stems of Al/icrocystis.

This form is closely related to H. untnrctictis, but has fewer tentacles, smaller anchors, and apparently a longer peduncle, although the stalk of H. antni-ctn-iis was probably con- tracted in PfefFer's preserved specimens. There are also color differences between the two forms.

Genus HALIMOCYATHUS Clark, 1863.

Halimocyathus, CLARK, 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 536.— AGASSIZ, A., 1865, North Amer. Acal., p. 61.

Halicvathus, HAF.CKEL, 1880, Syst. der Medusen, p. 393.

.\fanania, CLARK, 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 541.

The type species of this genus is H. platypus Clark, from Massachusetts Bay.

STAUROMI.m s K HA UM< X'YATHI s. 537

i.l M KK' CHARACTI KV

Stauromedusae with 4 perradial, gastrogenital pockets in the subumbrella wall ot the 4 stomach-pouches, as in Cleistocarpidae. \\ith S marginal anchors '4 perradial and 4 mter-

ladial I. S ail radial clusters of terminally knobbed tentacles. 4 interradial, horse-shoe-shaped gonads. 8 adradial arms.

This genus is very closely related to //<//;, lv.<tn\ . but is distinguished by the partitions across its 4 penailial Stomach-pouches, such as arc found in all Cleistocarpidae.

Halimocyathus platypus Clark.

Halimac\ailius fluty pus, CLARK, H. J., 186;, Journ. !'• Vit. Hist., \..l. ;, p. ,-,7.— AI.ASMZ, A., 1865, North Amcr.

Acal., p. 61. — HAECKEL, iSSo, Sy«t. del M dusen, p. 393. Lucernaria fltit\pus, TAS( H > NLMU:, 1877, Zeit. Ges. Naturw., Halle, p. 'i:.

Disk deep funnel-shaped, about 6 mm. wide, and iwith the peduncle) 10 mm. m height. The 8 arms are nearly twice as long as broad and one-third as long as bell-height from peduncle to margin. Each arm bears 17 to 20 thick, pistilliform tentacles, about as long as greatest breadth of arms; the tentacles upon each arm are arranged in 5 rows, there being about 7 tentacles in the middle row, 4 in each ro\\ on either side ot the latter, and one in each of the outermost positions. The 8 marginal anchors are small and reverted, being only one-third as lung as shortest tentacles, but proportionally broader; their length is a little less than 3 times their radial diameter. The peduncle is about halt as high as the disk; at the narrowest part, where it joins the disk. 1's diameter is nearlv halt its length, and from there it broadens into a wide base ha\ing a width equal to the length of the peduncle; it is round, or very slightly furrowed at 4 points opposite the 4 interradial muscles. The 4 separate, longitudinal chambers of the peduncle are very voluminous and close together, but the longitudinal septa between them are complete. 1 here are 4 horse-shoe-shaped gonads; the centripetal parts of each horse-shoe are united across the inner ends ot the 4 interradial parts while the tree, outer parts extend to the neighborhood of the marginal anchors. Each arm of the horse-shoe contains 15 to 17 genital sacs. The edges of adjacent gonads are joined by a cross partition as in other Cleistocarpidae.

A single specimen of this species was found by Clark at Chelsea Beach, Massachusetts, \\here it \\as found attached to Zostera, along with H. auricula. It has not been seen since Clark's day, and indeed the contamination of the sea-water in this region has destrou-d the Stauromedusnc which once abounded there, and which are now exceedingly rare along the entire New England coast.

Halimocyathus lagena Haeckel.

Hololhuria lagcna" Ml i i M , < >. I., i --6, Prodromus Zool. Danica, p. 232.

Lucernaria auricula, FACRKH:?, 1780, Fauna Gro*nlandica, p. 341. — MlLNE-EDWARDS, 1840. Cuvicr, Ki-gne Animal. Zoophytes,

planche 63, 9 figs. — SARS, M., 1860, Forliandl. Yid. Si-Uk., Christiania, p. 145. — KEFERSTHN, 1863, Zc.it. fiir wissen.

Zool., Bd. 12, p. 21. — TASCHENBXRG, 1877, Zcit. (n-s. Xaturw., Halle, p. 89. Lucernaria fabricii, ACASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 176. Lucernaria lyfiica, GREENE, 1858, Nat. Hist. Review, p. 132. Manania auricula, CLARK, H. j., 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 542. — AGASSIZ, A., 1865, North Amer. Acal.,

p. 62. Halicyathus lagena, HAECKEL, 1880, Syst. der Mcdusen, p. 394. — LEVINSFN, 1893, Vid. Meddel. Nat. For. Kjobenhavn (5),

Bd. 4, p. 147-

Bell urn-shaped, much deeper than broad. It passes from a rounded base abruptly into the peduncle. Bell about 5 to ~ mm. wide, and (including the style) about 20 to 30 mm. long. A cluster of 60 to /o slender tentacles upon the end of each of the 8 arms. Arms about as lung as broad and grouped into 4 interradial pairs. 8 marginal anchors have the same form as the knobbed tentacles, but are somewhat smaller. 4 horse-shoe-shaped gonads, the distal ends of which extend radially outwards are separated from the bell-margin by a wide space. Each horn of the gonads exhibits 12 to 14 genital sacs.

Color black or dark brown, rarely reddish-brown or yellowish-brown.

Found upon the northern Atlantic coasts of Europe and upon the coast of Greenland. It occurs on the New England coast north of Cape Cod, but is very rare.

538 MEDUSA OF THE WORLD.

(?) Genus CRATERLOPHUS Clark, 1863.

Craiertophus, CLARK, 1863, Journal Boston Soc. Nat. Hist., vol. 7, p. 539. — HAECKEL, i88o,Syst. der Medusen, p. 394. — GROSS, 1900, Jena Zeit. fiir Naturwissen, Bd. 33, p. 614. — MAAS, 1906, Fauna Arctica, Arktischen Medusen, Bd. 4, Lfg-3, p. 500.

The type species is Craterlophus tet/iys of Helgoland, German Ocean.

GENERIC CHARACTERS.

Stauromedusae with 8 adradial lobes and with 4 perradial gastrogenital pouches in the subumbrella wall of the 4 perradial stomach-pouches as in the Cleistocarpidae. Without per- radial or interradial marginal anchors or marginal papillae. The peduncle is 4-chambered.

According to Antipa, and Gross, this medusa may sometimes have 8 small tentacles, 4 per- radial and 4 interradial, in the places of the anchors of other Stauromedusae. It is probable, therefore, that Craterlophus is actually identical with Halimocyathus.

Craterlophus tethys Clark.

Lucernaria sp., METTENHEIMER, 1854, Abhandl. Scnckenberg, Naturf. Ges. Frankfurt, p. 15, taf. l, fign. 5-11.

Craterlophus tethys, CLARK, H. J., 1863, Journal Boston Soc. Nat. Hist., vol. 7, p. 540. — KLING, 1879, Morpholog. Jahrb., Bd. 5, p. 141, taf. 9-11. — HERTWIG, 1870, Jena. Zeitschr. fur Naturw.,Bd. 13, p. 613, taf. 9, fign. 7-12. — HAECKEL, 1880, Syst. der Medusen, p. 395. — CLAUS, 1883, Untersuch, Uber Organisation und Entwick. Medusen, p. 35. — ANTIPA, 1892, Zool. Jahrb., Abth. Syst., Bd. 6, p. 392, (aboral medusa). — GROSS, 1900, Jena. Zeit. fur Naturw., Bd. 33, p. 614, taf. 23, 24 (anatomy). — KASSIANOW, 1901, Zeit. fiir wissen. Zool., Bd. 69, pp. 299, 372, taf. 22, 24, 25.

Bell deep goblet-shaped, higher than wide, 15 to 25 mm. wide, and 25 to 30 mm. high, including peduncle. Peduncle short, 4-sided, prismatic, and 4-chambered, one-fourth to one- third as long as bell-height. Peduncle without longitudinal muscles. The 8 adradial arms are short, wide, and 45° apart. 60 to 80 knobbed tentacles upon each arm. There are normally no marginal anchors, although Antipa, 1892, and Gross, 1900, record abnormal specimens with 8 small tentacles, 4 perradial and 4 interradial.

The 8 gonads present the appearance of a 4-leaved cross, in the axes of which lie the 4 perradial, mesogomal pouches. The 8 arms of the gonads approach pair-wise and extend under the subumbrella from base of throat-tube to bell-margin with their proximal ends nearly touching. Each arm of the gonads has 10 to 16 feathery sinuosities and very numerous saccules.

Color variable, as in most of the Stauromedusae, being olive-green, yellowish, reddish- brown, or dark brown.

This form is found at Helgoland, German Ocean, where it lives upon the west coast of the island upon Ulva, Chorda, or FUCHS. Gross, 1900, gives the best description of its inter- nal anatomy. Kassianow, 1901 (p. 371), finds that if Craterlophus tethys be cut longitudin- ally from the oral pole to the middle of the peduncle, each half regenerates a new individual. If, however, the cut be not so deep the edges grow together and restore the former individual although the scar remains as a constriction upon the bell and pharynx. He also reports the finding of specimens of this medusa with more than 8 marginal lobes.

Craterlophus is imperfectly separated from Halimocyathus, bearing the same relation to it that Lucernaria does to Haliclystus. We may, however, retain these generic names mainly as a matter of convenience. In both Craterlophus and Lucernaria the perradial and interra- dial tentacles or anchors are commonly absent, but occasionally they appear as an abnormality and in such cases the medusae can not be separated from Halimocyathus and Haliclystus respectively.

Craterlophus macrocystis von Lendenfeld.

Craterlophus macrocystis, VON LENDENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 165; 1887, Australian Museum Descript. Catalogue Medusee Australian Seas, part I, p. 13.

Umbrella deep and bell-shaped, 12 mm. high, 6 mm. wide. Stalk 8 mm. high and 3 mm. wide when extended. 8 short arms 45° apart, each with a cluster of about 30 tentacles. Gonads feathery, as in C. tethys. Color dark olive-green. East coast of New Zealand on Macrocystis. Rare.

STAUHOMEDUS^E — CRATERLOPHUS, CAPKIA, LIPKEA. 539

The stalk of C. tmiLroscystis is two-thirds as long as the bell, whereas in C. tethys it is only one-fourth to one-third of this length. In other respects it resembles the very closely allied C. tetliys with which it may prove to be identical.

Genus CAPRIA Antipa, 1893. Cafria, ANTIPA, 1893, Mitth. Zool. Sta. Neapcl, Bd. 10, p. 628.

The type species is Capria siurdzii Antipa, from the Island of Capri, Bay of Naples, Italy.

GENERIC CHARACTERS.

Stauromedusae with S adradial, lappet-like arms which lack knobbed tentacles, but are each provided with a row of short, webbed, tooth-like or finger-shaped tentacles. \Yart-like clusters of nematocysts on subumbrella side of each of the 8 arms. No perradial or inter- radial tentacles or "anchors." The circular muscle of the subumbrella is entire, not divided into 8 isolated marginal muscles. The radial-muscle is funnel-shaped and spreads over the entire surface of the subumbrella. The 4 septal edges of the perradial stomach-pouches extend nearly to the bell-margin, where they are pierced by the ring-canal. 1 here is a long throat-tube, 8 adradial gonads, and an aboral stalk to the bell serving for attachment.

The genus Caftria is the only representative of the family Capriidas of Antipa, 1893, which may be defined as Stauromedusae with 8 adradial arms which lack knobbed tentacles, but have each a row of rudimentary tentacles joined by a web, one to the other. No anchors. Ring-muscles of the subumbrella entire, not separated into 8 isolated sectors. Longitudinal muscles equally developed over the entire subumbrella. Bell provided with an aboral stalk for attachment. Stomach with 4 simple, perradial pouches as in Eleutherocarpidae.

Capria sturdzii Antipa. Cafria siurdzii, AsrirA, iScj;, Mitlh. Zool. Sta. Neapcl, Bd. lo, p. 168, taf. 40, fign. 1-18.

Body g mm. long and 5.5 to n mm. wide; globular with a short, broad basal stalk or peduncle about as long as the bell-portion itself. Basal plate of peduncle or stalk of bell broad and flat and single-chambered, resembling a suctorial disk. There appear to be normally 8 short, thick, adradial, paddle-like arms, although the single specimen found had 10 arms; these are hollow and devoid of knobbed tentacles, but are provided with a row of if) to 20 tooth-like, or short finger-shaped, rudimentary tentacles which are fused one to another by a web. thus giving the appearance of a multi-toed, bird-like web-foot. There are 5 to 8 large clusters of nematocysts on the subumbrella side of each of the 8 arms. There are no "anchors" or suctorial tentacles, but the spaces around the bell-margin between the 8 arms are open and somewhat less in width than are the arms themselves. The circular muscle of the subumbrella is entire, not cut into 8 isolated muscles, as in certain other Stauromedusae. There are 4 rows of gastric filaments along the 4 interradial taeniolae from the middle of the central stomach nearly to the foot-plate. Mouth-tube long, prismatic, 4-sided, with 4 interradial, longitudinal furrows. Mouth-opening cruciform and quadratic. 8 band-shaped gonads, above (ahoral in reference to) the taeniolae. Color yellowish-white.

Found attached to a Serpula tube dredged from a depth of 40 fathoms near the Blue Grotto, Island of Capri, Bay ot Naples. It is described in detail by Antipa.

Genus LIPKEA Vogt, 1886. Lipkfa, VOC;T, 1886, Archiv. Sci. Phys. et Nat. Grntve, SIT. 3, tome 16, p. 356.

The type species is Lif>k?ti rusfoliana Vogt, from the coast of Sardinia, Mediterranean.

GENERIC CHARACTERS.

Stauromedusae with 8 hollow (4 perradial and 4 interradial) arms. With a continuous circular muscle. Neither tentacles nor "anchors." There are well-developed mucous glands upon the subumbrella. The bell is attached by a sucker.

540 MEDUSAE OF THE WORLD.

The only known species is described from a single specimen found attached to a Gorgonian at a depth of 50 fathoms off the Sardinian coast, Mediterranean. It is the only Stauromedusa having perradial and interradial marginal lobes, and Vogt places it in a new family, the Lipkeidae.

Lipkea ruspoliana Vogt.

Lipkea ruspoliana, VOGT, 1887, Mem. Inst. Nat. Genevois, tome 17, 53 pp., plates 10, n, figs. 1-17; 1886, Arch. Sci. Physique et Naturelles, Geneve, ser. 3, tome 16, p. 356.

Bell flat and soup-tureen-shaped with a very short basal stalk, by means of which the animal is attached. Bell f to 8 mm. wide, 4 mm. high, the basal stalk only 1.5 mm. long and 4 mm. wide. 8 short, blunt, hollow, marginal lappets, 4 perradial and 4 interradial in position. These lappets have plain, evenly rounded margins, and on their inner (centripetal) sides are about 15 to 20 large, oval mucous glands (containing nematocysts ?), the openings of which are scattered over the inner surface of each lappet. Subumbrella concave, but the central mouth is elevated and bordered by 4 cruciform lips. The 4 deep, conical (subgenital ?) ostia are interradial and alternate with the lips in position. Thus 4 of the 8 lappets are in the radii of the lips and 4 others are in the radii of the (subgenital ?) ostia. Ring-muscle entire, not divided into sectors, and extends around margin of subumbrella at bases of the 8 lappets. Longitudinal muscle-fibers extend radially outward from this powerful ring-muscle along the subumbrella faces of the 8 lappets. There are also a few weak, longitudinal muscles in the exumbrella near the stalk. There are neither tentacles, "anchors," nor other marginal appendages.

There are conspicuous clusters of gland cells in the ectoderm of the subumbrella. 4 large clusters are perradial in position and lie at the base of the 4 angles of the cruciform mouth- tube. There are also 8 linear clusters of these glands at the bases of the 8 lappets on the inner side of the ring-muscle. Central stomach divided by 4 interradial septa into 4 perradial chambers. These septa do not extend into the cavities of the 4 interradial lappets, so that the perradial chambers of the stomach communicate one with another through the cavities of these lappets. Stalk single-chambered.

No genital products were observed in the folded, membranous floors of the 4 (subgeniial ?) interradial ostia, but 4 pairs of branched, gastric filaments arise from the edges of the 4 inter- radial septa at base of oesophagus. It would seem that the medusa was immature and that the folded, follicular organs under the 4 ostia in the 4 interradii of the stomach are destined to develop the sexual products.

Medusa translucent to milky in color and the clusters of nematocysts on the subumbrella are yellow.

A single (immature ?) specimen was found by Vogt attached to a Gorgonian at a depth of 50 fathoms at Alghero on the northeast coast of Sardinia, Mediterranean. Vogt describes the specimen in detail.

CORONATE — PKRICOLPA. 541

Order CORONATJE Vanhoffen, 1892.

Discometluij: (in part), HAUCKKI., 1866, Generclle Morphologic, Bd. 2, p. 60; 1880, Syst. der Meduscn, p. 450.

C»ron,a.r, VA \nutt IN. 1892, Ergeb. dcr Plankton Exped., Bd. 2, K. c., p. zi; 1901, \Vissen. Krgcb. dcutsch. Ticfsee Exped.,

Dampfcr I'aldivia, Bd. 3, Lief, l, p. 11; 1906, Nordisches Plankton, Acraspede Mcdusen, Nr. 11, p. 41. Coronata, MAAS, 1903, Scyphomedusen dcr Siboga Expedition, Monog. 1 1, p. 5; 1907, Ergeb. FoitKhritte der Zool., Bd. I, pp. 191,

199. — BIGELOW, H. B., 1909, M< m. Mus. Comp. Zool. at Harvard College, vol. 37, p. 20.

CHARACTFRS OF THE CORONATJE.

Scyphomedusa; with marginal tentacles, a single central mouth-opening, and \vith the hell-margin clett into lappets. The rhopaha arise from clefts between these lappets, and their entodermal cores contain a terminal mass of crystalline concretions of entodermal origin. Ocelli may or may not be present. The medusie are free-swimming and have no aboral stalk for attachment.

With a circular, or coronal, furrow in the exumbrella, and peripheral to this there is a zone of gelatinous thickenings in the radii of the tentacles and sense-organs. These thickenings, or pedaha, are divided one from another by radiating clefts which alternate in position with the marginal sense-organs and the tentacles, and are in the middle (axial) lines of the marginal lappets. These marginal lappets project beyond the zone of the pedaha. The tentacles are solid, or not hollow, throughout their lengths. The throat-tube is simple, short, and provided with simple lips, without curtain-like appendages.

The families of the Coronats are as follows:

Periph\U'nLc CLAUS, 1886. 4 intcrradial rhopalia anil 4 or more tentacles.

Parapliylliniil.e MAAS, 1903. 4 perradial rhopalia and 4 or more tentacles.

Ephyropsidts CLAUS, 1883. 8 rhopalia (4 perradial and 4 interradial) and 8 or more tentacles.

Collaspitlx HAECKEL, 1880. Numerous rhopalia, alternating with an equal number of tentacles.

AtoreUitia: VA\H<UI>X, 1902. With 6 rhopalia and 6 tentacles.

Family PERIPHYLLID^E sensu Claus, 1886.

PeromeJusa: (in part), HAECKEL, 1880, Syst. der Medusen, p. 396.

Perifhyllijj, GLAUS, 1886, Class, der Me.lusen, Arbeit. Zo,.l. In t. Univ. VA'ien, Bd. 7, pp. 97-1 10.— VANHIH TFN, 1892, Akalephen

der Plankton Expedition, Bd. 2, K. d., p. 2 1 . — MAAS, iS9^, Mem. Mus. Comp. Zool. at Harvard College, vol. 23, No. i, p. 28;

1906, Fauna Arctic a, Bd. 4, Lfg. 3, p. eol . Y\\HI>H > \, i<|o6. \nr disc lies Plankton, No. 1 1, Acraspede Medusen, p. 41 . —

BII.M.OW, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 23. PtromeJustt, VON LENDENFELD, 1884, Proc. Linncan Soc. New South VA'.ili-s, vol. 9, p. 166.

FAMILY CHARACTERS.

Coronatae with 4 interradial pedaha which bear marginal sense-clubs, and with 4, or more, pedaha which bear tentacles.

The genera of the Periphylliclae are as follows:

Ptricolpa HAH KM, 1880, sensu Vanhoffen, 1902. With 4 prrradi.il tentacles, S adr.idul l.ippets, 8 gonads. Periphylla STEF.NSTRUP, 1837. With (4 X 3) 12 tentacle-. 4 perra.ii.il, S adrajial. id lappets, 8 gonads. Periphyllopsis VANHOFFEN, 1900. With (4 X 5) 20 tentacles, 24 l.ipi n . (?) Nauphantofsil KIWKIS, 1885; sensu Vanhfiffen, n)O2. \\'ith (4 X 7) 28 tentacles, 32 lappets.

Genus PERICOLPA Haeckel sensu Vanhoffen.

Ptrifolpa+- Pericr\ptci, HAICKM, iSSo, S^t. der Medusen, pp. 413, 414, 640.

Pericolpa, VANiiiJFFr-j, 1902, Wi <n. l.iri h. deutscli. Tiefs.-e I i .; ui, Bd. ^, Lfg. i , p. 50.- -MAAS, 1903, Scyphomedusen

dcr Siboga Expcd., Monog. ll, p. 12; 1906, Die Arktischen Medusen, Fauna Arctica, Bd. 4, p. 501.

GENERIC CHARACTERS.

Periphyllidae with 4 interradial rhopalia. 4 perradial tentacles, 8 adradial lappets. The 8 gonads are adradial or on both sides of the 4 interradii.

Haeckel's P?ricr\i>tu is doubtless only a more advanced stage in the growth of Pericolpa. The interradial t;i-iiiol;c are solid in the young, but become hollowed In the development of 4 pits in the floor of the subumbrella, and the gastral filaments increase with age. In the structure of the gastrovascular system this genus resembles Pcrif>li\lln, and were it not for the probability that the number of metameres apparently does not increase in the free eph\ ra

542 MEDUS.E OF THE WORLD.

of the Coronatae we would be inclined to regard Pericolpa as being only the young of Periphylla; for the development of 8 adradial lappets and 8 corresponding tentacles would change the medusa to Periphylla.

The species founded by Haeckel are separated upon slight distinctions, some of which represent mere stages in growth. Probably there are but two forms, P. quadrigata with an elongate, pointed bell and P. camfana with a flat, dome-like bell; but even this can not now be determined with any degree of certainty.

This genus includes the simplest and possibly most primitive of the Periphyllidae.

Pericolpa quadrigata Haeckel.

Pericolpa quadrigata, HAECKEL, 1880, Syst.der Medusen, p. 41 3, taf. 23,fign. 1-12; P. galea, Ibid., p. 41 4; ( ?) P.terralina, p. 640. — MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. II, p. 12.

Bell 40 mm. high and 30 mm. wide. The pointed, dome-like apical half of the exumbrella above the ring-furrow is as high as the width ot the pedal and lappet-zone below. The 4 perradial tentacular pedalia are somewhat wider than the 4 interradial, rhopalar ones and somewhat longer than the 8 marginal lappets. The 4 tentacles are about as long as bell- height. Throat-tube and stomach wide, rilling the greater part of bell-cavity. The basal part of the stomach leads into the gastrovascular space of bell by 4 perradial ostia, which are lined with gastral filaments. These ostia lead into a wide sinus which is interrupted by 4 short, partial septa in the interradii. Peripheral to these septa is another wide ring-sinus which sends out 8 canals in the radii of the sense-organs and tentacles. These radiating canals fork at their ends and extend around the edges of the lappets, forming a marginal ring-canal. The 8 gonads are grouped in 4 pairs on either sides of the interradii. Their inner ends are close together but they diverge outwardly. Color ( ?)

Found in the Antarctic, southeast of Kerguelen Island by the Challenger, and apparently identical with P. galia from the east coast of Australia.

Pericolpa campana Maas.

Pericrvpta campana, HAECKEL, 1880, Syst. der Medusen, p. 414.

Pericolpa campana, MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. n, p. 13, taf. 3, fign. 19-22.

Bell about 15 mm. high and 15 mm. wide, with thick gelatinous walls. A deep ring- furrow around exumbrella separates the evenly rounded dome-like center of bell from marginal zone of lappets. The 8 clefts between the 8 pedalia are also very deep. The 4 tentacular pedalia are nearly similar in size to the 4 pedalia of the sense-organs. The 4 tentacles are tapering and shorter than bell-radius. They are solid and their axial cores project into the gelatinous substance. These tentacles are situated in the perradii. Each of the 4 interradial marginal sense-clubs contains a terminal entodermal concretion and a ventral bulbular swelling, but no ocellus. The 8 marginal lappets are semicircular.

Stomach wide at base, and there are 4 interradial clusters, each with at least 30 gastric cirri. The stomach is connected with the gastrovascular space of the bell by 4 perradial openings. Peripheral to these there is a wide ring-sinus and this in turn gives rise to 8 radiating canals in the radii of the tentacles and sense-organs, and these fork and communicate one with another at their outer ends, forming a marginal ring-canal. The circular muscles of the subumbrella are well developed and there are radial-muscle strands near the bases of the tentacles. There appear to be 8 gonads. Maas records 7 of them irregularly arranged in a zone at middle of subumbrella, and Haeckel's specimen was so poorly preserved that he does not record the character of the gonads. Color (?)

Haeckel's specimen came from the region of New Zealand, while Maas records one from the Malay Archipelago, where it was obtained in a vertical net hauled from a depth of 500 fathoms in 17.6' S. lat., 129° 14.5' E. long.

This medusa is distinguished by its oval gonads.

Pericolpa tetralina Haeckel.

Perieolpa ietralina, HAECKEL, 1880, Syst. der Medusen, p. 640.

This medusa is probably identical with P. quadrigata, but both ends of the 8 gonads diverge from the 4 interradii, while in P. quadrigata only the outer ends diverge and the inner

CORONAT.E — PERICOLPA, PUdl'll VLLA. 543

ends approach one another closely. The medusa is very briefly mentioned by Haeckel and appears to be immature, being only 20 mm. high and 16 mm. wide. Found off the south coast of Australia. Described by Haeckel from a single preserved specimen.

Genus PERIPHYLLA Steenstrup, 1837.

Ptrifkylla,Situimtuf, 1837, Actaet Cat. Mus. Haf mends. — HAECKEL, i88o,Syst.derMedugen,p.4i8; 1881, Deep-sea Medusa? Challenger Report, Zool., vol. 4, p. 63. — CLAIS, 1886, Arbeit. Zool. lust. 1'niv. \Vien, Bd. 7, p. 99. — YANH'^KIN, 1892, Ergeb. Jer Plankton Exped., Bd. 2, K. d., pp. 4, 6, 21. — VON I.IM»NI KLD, 1884, Proc. Linnran Soc. New South Wales, vol. 9, p. 1 68. — MAAS, 1897, Mem. Mus. Comp. Zool. at Harvard College, \ • >!.:;, No. i, pp. 28-64; '9°4' Result. Camp. Sci. Prince dc Monaco, fasc. 28, p. 44; 1903, Scyphornedusen drr Siboga Expedition, Monog. 1 1, p. 5; 1907, Ergeb. Fort- schritte Jcr Zool., Bd. i, pp. 199, 219, etc.— VANHU'K FEN, 1902, Wissen. Ergeb. deutsch. Tiefs.ee Expedition, Dampfer I'uldivia, Bd. 3, Lfg. i, p. 21; 1906, Nordisches Plankton, Nr. ii,p.4i. — BIGELOW, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. ^4.

Periplifma, HAECKEL, 1881, Deep-sea Mcdus;c Challenger Exped., p. 84.

GENERIC CHARACTERS.

PeriphyllidaE with 4 interradial rhopaha, 12 tentacles, 4 perradial and 8 adradial. 16 marginal lappets grouped into 4 pairs of rhopalar and 4 pairs of tentacular lappets. A deep annular furrow separates the dome-like apex of the exumbrella from marginal zone of bell. Between this ring-furrow and the lappets is a zone of 16 pedalia, 12 in the tentacular and 4 in the rhopalar radii, and these are separated one from another by 16 deep, radiating clefts, which extend down the mid-axial lines of the lappets. There are 4 deep, interradial subgenital pus in the floor of the subumbrella, lined along their edges by rows of internal gastric cirri. The large central stomach extends peripherally outward into the subumbrella in the 4 perradii. These 4 openings lead into a wide ring-sinus in the subumbrella which in turn sends out a radiating vessel 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.

The 4 interradial septa are bordered by lines of gastric cirri and there are 8 U-shaped adradial gonads, one on either side of each septum. The tree ends of each gonad are directed inward toward the stomach, and their convexities point outward toward the bell-margin. The rhopaha have no ocelli, but contain a proximal mass of entodermal pigment and a distal concretion.

The medusae of Periphylla are deep-sea forms of very wide distribution. The so-called species are not well separated, being based on the relative height and width of the bell and on slight color distinctions. The bell appears to become relatively flatter as growth proceeds, and therefore its proportions would seem to afford a poor criterion for specific distinctions. Both Vanhoffen, 1902, and Maas, 1904, recognize but 3 species as follows:

P. hyacinthina ^ith IML;!), narrow bell, its height being to width as 44 to 23. Tin- l.ipprt pouches are dark-brown, so that

the gonads can not be seen through them from the outside. P. dodtcaboslrytha with bell flat, bluntly pointed, its height being to width as 27 to 18. Gonads visible through the lappets

from the outside.

P. regina with dome-like rounded bell and light red-brown color. Periphylla "mirabilis," Haeckel, appears to be identical with P. regina; and P. "humilis," Fcwkcs, appears to be an

imperfect P. doJtcabottrycha* P. peronii, Haeckel = Charybdea perifil:\llii, Peron et Lesueur, 1809, p. 332, is too

imperfectly known to be classified.

I think it probable that there is but a single species of Periphylla (P. hyacinthina), and that P. dodecabostrycha and P. n-gina are only varieties or local races. It is impracticable to attempt to separate species upon slight differences of form or proportions in their bells especially when such characters are sub]ect to constant changes due to growth or to state of contraction. Bigelow, 1909, who has studied many specimens of these medusx, concludes that P. hyacinthina and P. dodecabostrycha are identical.

Penpalma corona of Haeckel , 1880 (Sitzungsber. Jena. Gesell. fiir Med. und Naturw. Jahrg. 1880, Feb. 20; Syst. der Medusen, p. 418), is probablv a young Periphylla. Haeckel states that the genus is characterized by the absence of interradial pits or perradial concavities in the subumbrella, and that the 4 interradial taeniolz of the basal stomach are solid ligaments without gastral filaments.

544 MEDUSAE OF THE WORLD.

A single specimen was found by Haeckel at Algeciras in the Straits of Gibraltar. He states that owing to the general transparency of the specimen and to its smallness he is able to describe it only through reference to the larger species oiPeriphylla found by the Challenger expedition. He states that the bell is 30 mm. high, 20 mm. wide, helmet-shaped. The pedal zone nearly as wide as the lappet-zone. The 16 pedalia are of not quite equal size each to each. The 16 lappets tongue-shaped, sharp-pointed, the 8 tentacular more projecting than the 8 rhopalar lappets. 12 tentacles as long as the bell-height and one-third as wide as the lappets at their bases. Basal, central, and buccal stomachs of nearly equal length.

Color violet, bell more red, tentacles and throat-tube more blue, gonads dark-red.

Periphylla hyacinthina Steenstrup.

l'i-rifh\lla h\ac!nth!na, STEENSTRIT, 18(7, Acta Mus. Hafniensis. — HAECKEL, 1880, Syst.der Mcdusen,p. 419, taf. 24, fign. n- 16. — FEWKES, 1886, Report Commiss. Fish and Fisheries U. S. A., for 1884, p. 930. — CI.AUS, 1886, Arbeit. Zool. Inst. der Univ. Wien., Bd. 7, p. 99, fig. I, p. loo. — AGASSIZ, A., 1888, Bull. Mus. Comp. Zool. at Harvard College, vol. 15, p. 1-51, fig. 426. — VANHOKFEN, 1891, Zool. Anzeiger, Jahrg. 14, p. 38; 1908, Deutsch. Sudpolar Expedition, 1901-03, Bd. lo, Zool. 2, p. 36; 1892, Ergeb.der Plankton Expedition, Bd. 2, K. d., p. 6, taf. I, fign. l-io; taf. 2, fign. 3-8; taf. 3, fign. 1-7; 1902, Wissen. Ergeb. deutsch. Tiefsee Exped., Dampfer I'aldiria, Bd. 3, Lfg. I, p. 23; 1906, Nordisches Plankton, Nr. II, p. 42, fig. I. — BROWNE, 1903, Bergens Museums Aarbog, No. 4, p. 30. — MAAS, 1904, Result. Camp. Sci. Prince de Monaco, fasc.28, p. 47, plate 5, fig. 35; planche 6, figs. 45-46; ioc.6, Fauna Arctica, Bd.4, Lfg. 3, pp. 502,511 (review of literature). — BH.KLOW, H. B.. 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37. p. 26, plates 1 and 9.

Char\bdea hyacinthina, STEENSTRUP, 1842, Acta Mus. Hafniensis.

The following description applies to the typical P. hyacinthina.

This so-called species is distinguished by its high, narrow bell, the ratio of height to width being usually about as 44 is to 23. The lappet-pouches are so densely pigmented with dark purple-brown that the gonads can not be seen through them from the outside.

Bell 80 mm. high and about 42 mm. wide, but it may be much flatter and wider (see fig. 343). The upper, or aboral, halt ot the exumbrella is dome-shaped or pyriform with a smooth external surface. Just below this dome is a deep horizontal circular constriction which is occupied by circular muscle-fibers. Below this constriction the exumbrella flares slightly outward, and in this region we may distinguish an upper pedal-zone and a lower lappet- zone. The pedal-zone is divided by 16 deep, longitudinal furrows into the same number of projecting, wedge-like thickenings, the pedalia. The 4 interradial pedalia are smaller than the others and lie in the radii of the 4 marginal sense-organs; while the 12 perradial and adradial pedalia are situated in the radii of the tentacles.

There are 16 well-developed marginal lobes, arranged in 8 pairs. 16 deep longitudinal furrows lie in the mid-radial lines ot the lappets and separate the 16 pedalia, so that a furrow extends about two-thirds the distance down the exumbrella surface of each marginal lappet. The 4 interradial rhopalar clefts between the lobes are only about two-thirds as deep as the 12 tentacular clefts. Each sense-organ contains a proximal mass of dark-brown entodermal pigment and a distal concretion, which is protected by an aboral fold forming a niche for its protection.

The 12 tentacles are equally developed and are each a little longer than the bell-height. They are solid and are provided with well-developed, longitudinal muscle-fibers. In the cavity of the subumbrella 4 long, funnel-shaped, interradial pits extend inwardly along the sides of the central stomach nearly to the aboral apex, where their points do not quite touch. There is a well-developed zone of circular muscle-fibers in the subumbrella just above the bases of the tentacles and sense-organs. This zone is divided by 16 longitudinal selvages into 16 distinct parts; each selvage extends down the middle ot a lappet, and thus the ad|om- ing halves of each pair of adjacent lappets are connected by the circular muscles. Besides the circular muscles, 8 well-developed, longitudinal muscle-strands lie in the inner, or proximal, part of the subumbrella wall; 4 of these are perradial and 4 interradial. They are deltoid in shape, their broad bases extending out into the distal part of the subumbrella, to the upper part of the zone of circular muscle-fibers. There are 8 U-shaped gonads which are on both sides of the 4 interradial septa, with their convexities directed outward; thus they appear to be adradial in position and alternate with the 8 longitudinal muscles of the inner part of the subumbrella.

The stomach extends from the inner apex of the subumbrella to about the level of bell- margin. Its cavity may be divided into 3 regions, which we may designate, respectively

( i n;< i\ U K IM.IIII'liVr.LA.

545

as the basal, central, and buccal stomach. The central stomach is a 4-sided prism, the sides being interradial and the angles perradial in position. The lowi-r <u huccal part of the stomach hangs freely in the cavity of the bell, being joined to the subumbrellu at 4 perradially situated points at its inner end. There are 4 longitudinal, interradial, thickened regions in the wall of the buccal stomach, which extend downward to the mouth-opening. The central stoni.n h is a wide cavity which communicates hv 4 perradial openings with the gastrovascular space of the subumbrella of the medusa. These 4 openings are narrow, elongate, longitudinal clefts, and their edges are lined with numerous gastric cirri which project into the space of

Ptriphylla hyacintliina.

FIG. 342. — After Vanhbffen, in Valdivia Expedition.

FIG. 343. — After Vanhoffen, in Nordisches Plankton.

Showing variation in shape of bell.

the stomach. The basal stomach is a 4-sided pyramid and 8 rows of gastric cirri extend up the 4 sides near the angles to the apex of the pyramid where they meet. These rows of cirri are continuous with those surrounding the 4 perradial side-openings of the central stomach. The gastrovascular coronal sinus of the subumbrella is thus connected with that of the stomach by the 4 perradially situated ostia of the central stomach. These open into this wide annular cavity which occupies the mid-region of the subumbrella above the zone of circular muscles. Below these, however, it appears as a broad, simple, annular space, which extends outward

546

MEDUSA OF THE WORLD.

into the 16 marginal lappets. A partial septum extends, however, down the midline of each lappet, and the gastrovascular space forms a marginal ring-canal around these septa. Diver- ticula of the annular space also extend for a short distance into the bases of the tentacles, but the main entodermal cores of the tentacles are solid. A good idea of the structure of the gastrovascular cavity of the bell may be obtained from Vanhoffen's figure 3, taf. i, in "Ergeb. der Plankton Expedition," Bd. 2, K. d.

The inner surface of the subumbrella is purple, while the pedaha are copper-brown colored and the tentacles and lappets are of a milky-blue translucency. The gonads can not be seen through the densely pigmented bell-walls.

This deep-sea medusa is occasionally found upon the surface in the colder parts of the North Atlantic. It has been taken in the Bay of Biscay; at the Azores; off Cape Hatteras, North Carolina; at Martha's Vineyard; at Spitzbergen, and still more commonly off the coast of Greenland, but its true habitat is undoubtedly in the deep sea, at or near the bottom. Nearly all recent deep-sea expeditions record it, and the Valdivia found it in both the Atlantic and Indian Oceans. The best descriptions are those of Vanhoffen and Maas.

Haeckel states that the bell of this medusa may become 160 mm. high and 120 mm. wide, but later observers have not seen specimens of such great size.

Periphylla hyacinthina forma dodecabostrycha.

Chrysaora (dodecabostrycha) dubia, BRANDT, 1838, Mem. Acad. Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 387, taf. 29, 30. Periphylla dodecabostrycha, HAECKEL, 1880, Syst. der Medusen, p. 421. — VANHOFFEN, 1892, Ergeb. der Plankton Exped., Bd. 2,

K.d., taf. 2, fign. 1,2; 1908, deutsche Sudpolar Expedition 1901-1903, Bd. 10, Zool. 2, p. 35; 1902, Wissen. Ergeb. deutsch.

Tiefsee Exped., Valdivia, Bd. 3, pp. 21, 23. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. II, p. 6, taf. 2,

fig. 15; taf. 12, fig. 107 (figure of rhopalium); 1904, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 47, planche 5, figs.

36, 37; 1897, Mem. Mus. Comp. Zool. at Harvard College, vol. 23, p. 64, taf. u, fig. i. — MAYER, 1906, Bull. U. S. Fish

Commiss. for 1903, vol. 23, part 3, p. 1136, plate 3, figs. 5, 6.

non Periphylla dodecabostrycha, LOBIANCO, 1903, Mitth. Zool. Sta. Neapel, Bd. 16, p. 219, taf. 7, fig. 3 (this is a Paraphyllitta). ( ?) Periphylla humilis, FEWKES, 1886, Report Commiss. Fish and Fisheries U. S. A., for 1884, p. 931.

Bell higher than wide in young, wider than high in well-grown medusae. Thus when the medusa is 50 mm. wide the bell is 55 mm. high; when 45 mm. wide it is 45 high; and when 100 mm. wide it is 70 mm. high.

The gonads may usually be seen through the gelatinous walls of the bell, but not so clearly in old as in young specimens. Thus the bell is said to be lower, flatter, and less pointed than in P. hyacinthina, and the bell-walls are more transparent.

Widely distributed over the floor of the great oceans, and especially in tropical parts of the Pacific, west coast of Mexico, coast of Chile, Hawaiian Islands, Philippine Islands, Indian Ocean, Malay Archipelago, Mediterranean, Guinea Stream ofF Atlantic coast of Africa.

It is probably only a variety of, or even only a growth-stage of, P. hyacinthina.

Periphylla hyacinthina forma regina.

Periphylla regina, HAECKEL, 1880, Syst. der Medusen, p. 421; 1881, Deep-sea Medusx Challenger Exped. Report, Zool., vol. 4, p. 85, plates 24, 25. — MAAS, 1897, Mem. Museum. Comp. Zool. at Harvard College, vol. 21, pp. 29, 64, taf. 10, i fig.; 1903, Scyphomedusen Siboga Exped., p. 6. — VAN- HOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Exped., Valdivia, Bd. 3, Lief. I, pp. 21, 23; 1908, deutsche Sud- polar Expedition, 1901-1903, Bd. 10, Zool. 2, p. 36.

Periphylla mirabilis, HAECKEL, 1880, Syst. der Medusen, p. 442; 1881, Challenger Exped. Report, Zool., vol. 4, p. 64, plates 18-23, 4° fiSs-

This appears to be merely a light violet or rusty-reddish variety of P. hyacinthina. Bell usually low, dome-like, about i 50 mm. wide, and

rio. 344. — Periphylla regina, after Vanhoffen, in . ; I-IITTII

Tiefsee Expedition Valdivia. nearly 1.5 times as wide as high, but Haeckel

CORONATVE — PERIPHYLLA, PERIPHYLLOPSIS.

547

records a specimen fully as high as wide. According to him, the pedalia are rectangular and longer than wide, but according to Maas, 1897, they are nearly circular in outline. The tentacles are said to be short and thick, and the stomach very large and wide, but these points as well as the proportions of the bell, are probably affected largely by growth and contraction.

Found on the bottom of the Pacific and Atlantic from the Antarctic regions to the tropics.

It is the largest form of Pcriphylla and may become 200 mm. wide.

Genus PERIPHYLLOPSIS Vanhoffen, 1900.

Ptriphyllofisii, VANHOFFEN, 1900, Zool. Anzciger, Bd. 23, p. 278; 1902, Wissen. Ergeb. dcutsch. Tiefsee Esped., 1'alJivla, Bd. 3, Lfg. I, p. 27. -MA*S, 1907, Ergcb. und Fortschrittc der Zool., Bd. i, p. 195. — BIGELOW, H. B., 1909, Mem. Mus. Comp. Zoo], at Harvard College, vol. 37, p. 27.

The type species is Ptriphyllopsis braueri Vanhoffen, of the Indian Ocean; from a depth of 1,200 fathoms.

GENERIC CHARACTERS.

4 interradial rhopalia, 4X5 (20) tentacles, 4X6 (24) lappets.

Periphyllopsis braueri Vanhbffen.

Peri fliyllaf sis braueri, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Dampfer Faldivia, Bd. 3, Lfg. i, p. 27, taf. 2, fig. 7. — BIGELOW, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 28, plates 9 and 12.

Vanhoffen's single specimen was so imperfect that he could not venture to present a detailed description of it. Recently, however, Bigelow describes a more nearly perfect specimen

345-

Periphyllopsis braueri.

FIG. 345. — After Vanhoffen, in I'alJivia Expedition. Aboral view of hell. FIG. 346. — With the walls of the stomach torn away leaving only its base with the gastric cirri. After H. B. Bigelow, in Mem. Museum Comp. Zool. at Harvard College, 1909.

from the collections of the Albatross, and the account here given is mainly derived from his description.

Bell flattened, 60 mm. wide and 25 mm. high, resembling an Atolla in shape. Central disk about 50 mm. wide; ring-furrow deep. 4 interradial rhopalia, 24 (4x6) ovate marginal lappets, and 20 (4x5) tapering tentacles, about as long as the bell-diameter. Thus the radial arrangement of the various organs is the same as is seen in Periphylla, only the numbers of lappets and tentacles being greater. The ring-muscle of the subumbrella is very weak as in

~>1S MEDUSA OF THE WORLD.

Atorella. The peripheral canal-system resembles that of Periphylla. The central stomach opens into a wide ring-sinus by 4 perradial ostia separated by 4 interradial septa. The ring- sinus is about 10 mm. broad and is at the zone of the gonads. On its outer side it gives off 24 broad, spoke-like radial-canals in the radii of the rhopalia and tentacles, and these canals are connected one with another by a festoon ring-canal at the margin, extending in loops around the lappet margins. There are 8 oval gonads, adradial in position and equidistant one from another. The mouth parts were lost in both Vanhoffen's and Bigelow's specimens, but there are about 80 to 100 simple gastric cirri arranged in a single linear row. There are 4 inter- radial ostia in the subumbrella. The entire entodermal system is chocolate-red.

The Valdivia specimen was dredged from between 1,200 fathoms and the surface in the Indian Ocean between New Amsterdam and Cocos Islands, and the Albatross specimen which was studied, while yet alive, by Bigelow was obtained in the Humboldt current off the coast of Peru between 400 fathoms and the surface.

Genus (?) NAUPHANTOPSIS Fewkes, 1885.

Nauphanlopsis, FEWKES, 1885, Report Commiss. Fish and Fisheries U. S. A. for 1883, p. ^96; 1886, Report Comrniss. Fish and Fisheries U. S. A. for 1884, p. 944. — VANHOFFEN, 1892, Ergeb. der Plankton Expedition, p. zi; 1902, Wissen. Ergeb. deutsch. Tiefsee F.xpeJ. t'aldivia, Bd. 3, Lfg. I, p. 51. — HARGITT, 1904, Bulletin I'. S. Bureau of Fisheries, vol. Z4, p. 66. — MAAS, 1907, Ergeb. und Fortschritte der Zool., Bd. I, p. 199.

GENERIC CHARACTERS.

Coronatae with 32 marginal lappets, 4 interradial sense-organs, and 28 tentacles. With an annular furrow and 32 radial ridges (or pedalia) upon the exumbrella in the radii of the tentacles and sense-organs.

O

Owing to the incompleteness of our knowledge of the only known species of this genus it must remain problematical.

Nauphantopsis diomedeae Fewkes.

Nauphanlopsis diomedfee, FEWKF.S, 1885, Report Commiss. Fish and Fisheries U. S. A. for 1883, p. 596; 1886, Report Commiss. Fish and Fisheries U. S. A. for 1884, p. 946, plate 6, figs, i, 2; 1888, Amer. Journ. Sci., ser. 3, vol. 35, p. 173; Ann. and Mag. Nat. Hist., ser. 6, vol. i, p. 255. — HARCITT, C. W., 1904, Bull. U. S. Bureau of Fisheries, vol. 24, p. 66.

Fewkes gives an unsatisfactory account of this medusa owing to the poor preservation of his material. We are uncertain whether there are 4 or 8 marginal sense-organs.

Disk quite flat, 70 mm. in diameter. Central part of exumbrella flat and surrounded by an annular furrow; diameter of this region about 35 mm. Centrifugally from the annular furrow there is a zone about 10 mm. wide consisting of 32 radial elevations separated by 32 deep radial furrows; these elevations lie in the radii of the tentacles and sense-organs and alternate with the lappets. Each elevated ridge is bifurcated at its outer end by a deep median cleft. The 32 lappets are long and rectangular with rounded outer edges. They are each about 10 mm. long and 8 mm. wide. There are 4 or 8 ( ?) marginal sense-organs and 24 ( ?) or 28 tentacles. The sense-organs were not observed in the specimen studied by Fewkes. Tentacles slender and flexible and about 80 mm. in length. Subumbrella (?) Mouth (?) Gonads (?) Color (?)

A single specimen was dredged from a depth of 2,033 fathoms in N. lat. 38° 30', W. long. 69° 8'.

Family PARAPHYLLINIDvE Maas, 1903. Paraphyllinidtc, MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. n, p. 6.

FAMILY CHARACTERS.

Medusa Coronates with 4 perradial rhopalia and 4 or more tentacles.

This family differs from the Periphyllidas only in having the marginal sense-organs perradial instead of interradial.

There is only one known genus among existing medusje, this being Paraphyllina; but this is very closely related, if not identical, with Paraphyllites, a fossil medusa of the litho- graphic slate of Kelheim.

Maas records a Paraphyllina from the Malay Archipelago, and another specimen was taken by the Krupp yacht Puritan at a depth of 500 fathoms, near Capri, Bay of Naples.

CORONAT/E — PARAPHYLLINA. 549

Genus PARAPHYLLINA Maas, 1903.

Parapln'llina, MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, p. 6; 1907, Ergeb.urul Fortschritte dcr Zool., Bd. I, p. 195.

The type species is Paraphyllina intermedia Maas, 1903; from the Malay Archipelago, between 100 fathoms and the surface.

GENERIC CHARACTERS.

Coronatae with 12 tentacles, 4 perradial marginal sense-organs, and 1 6 lappets. The 12 tentacles are interradial and adradial with reference to the stomach and lips. There are 4 pairs (8) of interradial gonads. The marginal sense-organs have a terminal lithocyst-sac and a ventral bulb-like swelling, just beyond which is an eye with ectodetmal lens and ecto- dermal pigment.

The short 4-sided throat-tube and flat disk-like bell resemble the condition noted in Nausithoe. but in its 4 marginal sense-onrans and 12 tentacles it recalls the condition seen in

i O O

Periphylla, with the important difference that in Periphylla the sense-organs are interradial, whereas in Paraphyllina they are perradial in position.

Maas places this genus in a new family which he calls the Paraphyllinidae. The characters of this family are those ot its only genus, Paraphyllina. It is closely related to the fossil genus Paraphyllites, Maas, 1906 (Neuen Jahrbiich. tiir Mmeralogie, Geol. und Palaontol., Bd. 12, p. 90, 4 fign.). This lossil medusa differs from recent Paraphyllina only in that its 8 gonads are adradial and placed 45° apart, whereas in Paraphyllina they are grouped in pairs on both sides of the 4 interradii.

Paraphflhtrs disttnetus is described by Maas from a well-preserved specimen. It is 15 mm. wide and has a well-developed coronal furrow, 16 pedaha, 4 perradial marginal sense-organs, 12 tentacles, and 8 adradial gonads 45° apart. It is from the lithographic slate of Kelheim. The latest reference to this fossil is that of von Ammon, 1908, Geonostischen Jahiespeften, Jahrg. 19, p. 170.

Paraphyllina intermedia Maas.

Paraphyllina intermedia, MAAS, 1903, Scyphomeduscn dcr Siboga Expedition, Monog. II, p. 8, taf . 2, fign. 10-14; taf. 1 1, fig. 106. Periphylla dodecabostrycha, LOBIANCO, 1903, Mitth. Zool. Sta. Neapel, Bd. 16, p. 219, taf. 7, fig. 3. See aku MAAS, 1^04, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 48, foot-note.

Bell flatly rounded, 8 mm. high and 15 mm. wide, without pointed apex. The coronal furrow around the exumbrella is deep and separates the smooth, central, flatly-rounded apex of exumbrella from the marginal zone ot lappets. Lappet-zone about as wide as radius of central disk of exumbrella. The 16 pedaha ot the marginal zone are rectangular with rounded angles and are separated one from another by deep radiating furrows. These pedalia are in the radii of the tentacles and sense-organs and alternate with the lappets. The 12 pedalia of the tentacles are of uniform width, while the 4 pedalia of the marginal sense-organs are only about half as wide as the former. The 16 marginal lappets are oval and bluntly pointed, and the 8 lappets flanking the 4 sense-organs are somewhat narrower than the others. The 12 tapering, hollow tentacles are all of equal length and are not quite as long as the diameter of the bell.

The 4 marginal sense-organs are each covered by a hood-like fold of the exumbrella. Each sense-club contains a small terminal sac-shaped entodermal concretion. On the ventral (subumbrella) side of the sense-club is a large ectodermal eye with a cup-like mass of pig- ment and a spherical lens. On the inner side of the eye and upon the ventral side of the sense-club is a bulb-like swelling. Altogether the sense-clubs resemble those of Nausithoe, but the eye is larger.

The throat-tube is short and 4-sided and the mouth is a simple cruciform opening. There are 4 interradial rows of gastric filaments. The coronal ring-canal gives rise to 16 peripheral pouches in the radii of the sense-organs and tentacles, and these are put into communication one with another by means of a marginal ring sinus, as in Nausithoe.

The gonads resemble those of Palephyra and are intermediate in character between those of Periphylla and those of Nausithoe. They consist of 4 pairs of bean-shaped or egg- shaped sacs. These 8 sacs project from the subumbrella floor on both sides of the 4 inter- radii near the sides of the throat-tube and centripetal to the ring-muscle.

550

MEDUSA OF THE WORLD.

There is a well-developed ring of circular muscle-fibers in the subumbrella, beyond the gonads and inside oi the insertions of the tentacles. This zone of ring-muscles appears broken in the mid-radii of the lappets, thus forming 16 trapezoids in the radii of the sense- organs and tentacles. Radial-muscle strands extend outward in the tentacular radii and con- verge at the bases of the tentacles.

The medusa is colorless save for the pigment of the eyes in the marginal sense-organs and for 4 interradial masses of red-brown pigment in the central stomach, leaving a clear cruciform space between them.

Two specimens were taken by the Siboga in the Malay Archipelago, in vertical nets, from a depth of 100 fathoms, at 6° 2' S. lat., 123° 577' E. long.

Dr. Lobianco describes a similar medusa in the collection made by the Krupp yacht Puritan, from a depth of 500 fathoms, near Capri, Bay of Naples. He generously permitted me to study the very well-preserved specimen of the medusa in the Zoological Station at Naples. It resembles Maas's specimens from the Malay Archipelago except that the gonads

FIG. 347. — Parapln'llina intermedia. From a specimen in the Naples Zoological Station.

(female) are more slender and their outer ends somewhat longer than in the Malayan speci- mens. There are 4 deep interradial, crescentic pits in the floor of the subumbrella between the gonads and the gastric cirri. The medusa was 15 mm. wide and in all respects (save in the minor details mentioned above) it appears to be identical with the East Indian medusa. A figure of Dr. Lobianco's medusa drawn by me from his specimen is presented in fig. 347.

Family EPHYROPSID.& Claus, 1883.

o/>siWtf, CLAUS, 1883, Organisation und Enrwick.Meduscn, pp. 23, 24; 1886, Arbeit. Zool. Inst. Univ. Wien., Bd.y, pp. 99, no. — VANHOFFEN, 1892, Ergeb. der Plankton Expedition, Bd. 2, K. d.,p.2i. — MAAS, 1897, Mem. Mus. Comp. Zool. at Harvard College, vol. 23, p. 65; 1907, Ergeb. und Fortschritte der Zool., Bd. I, p. 2 1 1 .— Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, pp. 21, 33.

idjt+Linergidtf, HAECKEL, 1880, Syst. der Medusen, pp. 476, 490.

FAMILY CHARACTERS.

Coronatse with 8 rhopalia (4 perradial and 4 interradial). 8 or more tentacles and 16 or more lappets. Mouth surrounded by 4 short, simple lips. 4 perradial ostia connect the central stomach with a wide ring-sinus. Peripherally this ring-sinus of the subumbrella gives rise to

CORONATVE — PARAPHYLLINA, PALEPHYRA. 551

1 6 radiating pouches in the radii of the sense-organs and tentacles; these pouches are separated one from another by 16 septa in the radii of the lappets. These septa may be complete or incomplete; and when incomplete there is a communication between adjacent pouches at the bell-margin forming a peripheral ring-canal.

The Ephyropsidae are creatures of the open sea and are very widely distributed, but are especially abundant in the tropics. In the case of Nausithoe the scyphostoma larva bears a superficial resemblance to a branching hydroid, and it infests sponges. The ephyra is produced by strobilization.

The genera of the Ephyropsidae are as follows:

Palephyra HAECKEL, 1880 (sens. ampl.)= Epii\ra + Paleph\ra + Zoneph\ra Hacckrl. 8 adrajial tentacles, 16 lappets,

4 interradial gonads. Nautithoe KOLLIKER, 1853= Nausicaa + Nausilhoc + Natiphanta Haeckcl. 8 adradial tentacles, 16 lappets, 8 .ijr.nii.il

gonads. No subumbrella saccules. Linuche ESCHSCHOLTZ, i&2<)= Linergcs + Linhcus + Linuche Haeckel. Similar to \ausitlioi, but with sac-like gastric

pouches upon the subumbrclla.

Genus PALEPHYRA Haeckel, 1880.

Epltyra+Paltphyra + Zoncphvra, HAECKEL, 1880, Syst. der Medusen, pp. 482-484, 641.

Palephyra, VANHOFFEN, 1901, Wissen. Ergeb. deutsch. Tiefsee Eipedition, Dampfer FalJlvia, Bd. 3, Lfg. I, p. 31; 1908, deutsche Sudpolar Expedition, Bd. 10, Zool. 2, p. 38.

The type species is Palephyra antigua Haeckel, from the Red Sea.

GENERIC CHARACTERS.

Coronatae, with 8 adradial tentacles, 8 (4 perradial and 4 interradial) marginal sense- organs, 16 lappets, and 4 interradial gonads.

This genus is related to Nausithoe, but is more prim- itive in that there are but 4 interradial instead of 8 adradial genital organs as in Nausithoe. Indeed, in Nausithoe itself the gonads begin to develop in the 4 interradii, but later they divide and migrate into the 8 adradii.

Haeckel distinguished three genera of medusae with 8 tentacles, 8 sense-organs, 16 lappets and 4 interradial gonads: (l) Ephyra, without lappet-pouches; (2) Pale- phyra, with 8 cleft lappet-pouches in the ocular radii; (3) Zonephyra, with 1 6 cleft lappet-pouches in the rho- palar and tentacular radii. Haeckel, however, cut no sections and his ideas of the structure of the gastric cavity are probably erroneous. His Ephyra is apparently FIG. 348.-" Ephyra proper'' Af«,-r oniy an immature stage of Palephyra, which is in turn

Haeckel, in Das Syst. der Medusen. • , • . , ~ ' *

identical with Zonephyra.

"Zonephyra corona" Agassiz and Mayer, 1902 (Mem. Museum Comp. Zool. at Harvard College, vol. 26, p. 157), is apparently a young Pelagia.

Palephyra antiqua Haeckel.

Ephyra prometor (young medusa), HAECKEL, 1880, Syst. der Medusen, p. 482, taf. 27, fign. i, 2. Palephyra primigenia (half-grown medusa), HAECKEL, Ibid., p. 483, taf. 27, 6gn. 3-6. Pelephyra antiqua (adult [ ?] medusa), HAECKEL, Ibid., p. 484.

Bell 20 mm. wide, 8 mm. high. Coronal furrow and pedalia ( ?), 8 adradial tentacles about half as long as bell-radius. 8 sense-organs; 16 spatula-shaped, sharply pointed lappets, half as long as bell-radius. A long 4-sided oesophagus with folded, recurved lips. 4 inter- radial gonads divided in the 4 perradii; each gonad crescent-shaped with the horns recurved. 6 to 8 slender gastric cirri in each interradius.

Tropical Indian Ocean near Madagascar.

Haeckel describes that which I take to be the young of this medusa zsEph\>ra(Archeph\ra) prometor from the coast of Australia. It is only 8 mm. wide and has 4 simple, interradial,

552

MEDUSAE OF THE WORLD.

crescent-shaped gonads, each with only one gastric filament. His Palephyra primigenia appears to be the half-grown medusa. There are only 2 gastric cirri in each interradius, and the gonads and tentacles are said to be light-reddish, nearly colorless. It comes from the Red Sea, near Tur.

Palephyra pelagica.

Zoneplivra zonaria (young medusa), HAF.CKEI., 1880, Syst.

der Medusen, p. 484, taf. 27, fign. 7, 8. Zonfph\ra pelagica, HAECKF.L, Ibid., p. 485.

Bell 12 mm. wide, 2 mm. high, with a coronal furrow. Mouth-tube wide and short, hardly one-third as long as bell- diameter (contracted ?). 1 6 spatula- shaped, pointed lappets, half as long as bell-radius. 8 adradial tentacles not quite half as long as bell-radius. 4 half-moon- shaped interradial gonads with ends of crescent pointing outward. Each gonad consists ot 3 swellings; the middle part being hardly halt as large as the two lateral ones. JO to 12 short, gastric cirri in each interradius. Color (?) Coast of Japan. Haeckel describes that which may be a young stage of this medusa under the name of Zonephyra zonaria. It is only 8 mm. wide. The mouth tube and tentacles are longer than in P. pelagica, but this may be due to conditions of contraction. The median and terminal swellings of each gonad are all of the same size. Found off the coast of China. Haeckel's Zonephyra conncctens (System der Medusen, p. 641), from the tropical Pacific is said to differ from those described above in having each gonad composed of 2 swollen regions instead of 3 as in his

FIG. 349. — "Zonephyra zonaria," after Haeckel, in Das Syst. der Medusen.

35°

FIG. 350. — Palephyra " prim i gen ia" after Haeckel in Das Syst. der Medusen. FIG. 351. — Palephyra Jndica, after VanhofTen, in Valdivia Expedition.

COUONAT.E — PALKPIIYRA, XAUSITHOE. 553

7,. pflavica. There are also 4 lanceolate, complexly folded lips. The medusa is only JO mm. wide and is probably an immature stage.

Palephyra indica Vanhbffen. Palephvrainiii(a,\ \\uittfTK, ¥.., 1902, Wisscn. Ergeb. deutsch. Tiefsee Expedition, Dampfer F0/</i'r/3, Bd. 3, p.ji, taf.j,fig. 10.

Hell 12 to 16 mm. wide. 8 adradial tentacles, 8 marginal sense-organs, 16 marginal lappets. 4 large, bean-shaped interradial gonads wider than the spaces between them. About 80 simple gastric filaments. Hell white, with faint brown, radial punctations in the radii of the sense-organs and axial lines of the lappets. Stomach brown. Cult ot Aden from a depth of about 500 fathoms.

Vanhoften presents a beautiful figure of this medusa, drawn Irom lite.

Genus NAUSITHOE Kblliker, 1853.

MIUJI//IO?, KOLUKER, 1853, Zeit. fur wissen. Zool., Bd. 4, p. 323. GEGINBAUR, 1856, Zeit. fur wissen.Zoo!., B!. s, p. 111.-

II ; r.i m ., c '.. mi I K., iS-s. \i-nL-n \ .1. unil Sinn i . i M .".-n,p. 105. — GLAUS, 1883, Organisation Entwick. McJu-

s<-n, p. 24. — VANH ii ' . . [892, Erg b. ;« i l'l,m].i< -n I. \pr,!iu«n, p. 21 ; 1902. Wissen. Kri;eb. deutsch. Tiefsee Expedition,

Dampfer I'aldh-ia. Bil. -,, Lfg. i, pp. 28, 30; 1906, Nordisches Plankton, Nr. n, p. 43.— MAAS, 1904, Result. Camp. Sci.

I'n 1 1. .• de Monaco, fasc. 28, p. ;;, ; i')o;, S, tpimmr-dusen der Siboga Exped., Monog. u, p. 18. — Bicetow, H. B:, 1909,

Mem. Mus. Cdinp. 7.<><>l. at Harv ird I ill' L^ . nd. 5", p. ',-,. Oclogonia, MULLER, J., 1854, Muller's Archiv. fiir Anat., etc., p. 97. 'apsis, GF.OENHAUR, 1856, Mullet's Archiv. fur Anat., etc., p. 239.

,1,1 I \ausiihnr t \'au [ihanla, HAKCKKI., 1880, Syst. dcr Mrduscm, pp. 486, 487. Scyphostoma larva:

Spwgicola fstularis, SCHVLTZE, T. E., 1877, Archiv. fiir Mikroscop. Anatomic, Bd. 13, p. 795.

Stephanosc\ft/ius mirtibilis, AU.MAN, iS~4, Annals and Mag. Nat. Hist., SLT. 4, vol. 14, p. 237.

Xtiittitfwf, I.'ii:iA\ro, S., umi MA^JR. P., 1890, Zool. Anzeiger, Jalir^- 13, p. 687.

The type species is N. [>uiift<it<i of the Mediterranean, Atlantic, Pacific, Indian, and Arctic Oceans.

GENERIC CHARACTERS.

Ephyropsidae with S (4 perradial and 4 interradial) marginal sense-organs and 8 adradial tentacles. There are i'< marginal lappets and 8 separate adradial gonads, the gonads isolated, not grouped in pairs. The central stomach communicates with a wide ring-sinus in the bell by means of 4 perradiallv situated ostia; the 4 interradial septa between these openings give rise to the entodermal gastric cirri. Peripherally, the ring-sinus gives forth 16 simple, unrami- fied pouches in the radii ot the sense-organs and tentacles. The partitions between these pouches are not complete, for there is a marginal ring-canal. No saccules on the subumbrella.

\\ < may possibly distinguish the following "species" of Nausithoe:

\ . i-u'!' f<r . punctured, central disk without radiating furrow^ l.iu-f t/"M.i.!s, gastra! filaments not gi

into clusters. All oceans.

N. clausi, with smooth central disk, small gonads- Caroline Islands, Pacific. A', cballengrri, central disk with radiating furrows. Tristan d" Acunha, Snutli Atlantic. A', albatroai, smooth central (!r !,, 1 >!u- . narrow marginal lappets. Gastral filaments grouped into clusters, with a numher

of sep. ii ite ' In f'Ts in each interrajius. Gulf of Panama, Pacific Ocean. .V. rubra, red color. Pitted central disk. Simple gastral filaments which are not grouped into clusters. Indian and

South Atlantic Oce.ins=A'. pniirtiila (?) N. picta, similar ti> \ . .NjrnMM, but with chocolate-brown or carmine gonads and blue gastric cirri = \. punciata ( ?).

It is apparent that there are onlv 4 well-marked forms of Naiisithoe: (i) the punctata, rulini, fiiitii group \\ith pitted central lens which lacks radiating furrows, and with gastric filaments arising singly, not in clusiers; (2) .V. cLnifi with smooth central lens; (3) A. albatrosst with gastric filaments grouped in clusters; (4) A . fliallfn«i-n with radial furrows upon the central lens.

The scyphostoma larva of Naiisithoe infests sponges and bears a superficial resemblance to a branching hydroid. See N. f>iin,-t,iiii. I he medusa ot A ausithoe is peculiar in having clusters of small crystals scattered at intervals within the ectoderm of its umbrella.

554

MEDUS.E OF THE WORLD.

Nausithoe punctata Kolliker.

Plate 60, figs. 4 and 5.

Nausithoe punctata, KOLLIKER, 1853, Zeit. fiir wissen. Zool., Bd. 4, p. 323. — KEFERSTEIN und EHLERS, 1861, Zool. Beitr. Neapel, Messina, p. 80, taf. 13, fign. 1-3. — HAECKEL, 1880, Syst. der Medusen, p. 486. — CLAUS, 1883, Organ, und Entwick.der Medusen, pp. 24, 41, taf. 6, fign. 44-466; taf. 7, fign. 47-53; taf. 8, fign. 54~55d. — HAMANN, 1883, Zeit. fiir wissen. Zool., Bd. 38, p. 420, taf. 23. — GRJEFFE, 1884, Arbeit. Zool. Inst. Wien., Bd. 5, p. 342 (at Trieste, Adriatic, June to Oct., rare). — VANHOFFEN, 1892, Ergeb. der Plankton Expedition, Bd. II, K.d., p. 13, taf. 3, fign. 8, 9; 1892, Ergeb. der Plankton Expe- dition, Bd. 2, K. c., Nachtrag; 1902, Wissen. Ergeb. deutsch. Tiefsee Exped., Bd. 3, Lfg. i, p. 29; 1906, Nordisches Plankton, Nr. 1 1, p. 43, fign. 2, 3 (North Atlantic 59° 39' N. lat.): 1908, deutsche Siidpolar Expedition, Bd. 10, Zool. 2, p. 37. — MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard College, vol. 37, p. 67, figs. 67, 86; plate 23, figs. 87, 88; plate 26. — AGASSIZ, A. and MAYER, 1902, Mem. Museum Comp. Zool. at Harvard College, vol. 26, p. 155, plate 7, fig. 32. — BIGELOW, H. B., 1904, Bull. Mus. Comp. Zool. at Harvard College, vol. 39, p. 263, plate 6, fig. 21 (Maldive Islands, Indian Ocean). — MAAS, 1904, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 54. — BROWNE, 1905, Report Pearl Oyster Fisheries, Gulf of Manaar, p. 157. — BIGELOW, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 35, plate 12.

Nausithoe albida, GEGENBAL R, 1856, Zeit. fiir wissen. Zool., Bd. 8, p. 21 1. — CARVS, i857,IconesZootom., taf.II, fign. 17, 22, 23. — HERTWIG, O. und R., 1878, Nervensyst. und Sinnesorgane der Medusen, p. 105, taf. 9, figs. 2, 5, 10-13; ta^' Io» ^6' 17*

Nausilhoe punctata, var. polaris, MAAS, 1 906, Fauna Arctica, Bd . 4, Lfg. 3, p. 51 1 = Nauphanta polaris Fewkes (review of literature).

Nauphanta vttloris pisani, VANHOFFEN, 1892, Ergeb. der Plankton Expedition, Bd. 2, K. d., p. 15, taf. 3, fig. 10.

Nauphanta polaris, FEWKES, 1888, Report Lady Franklin Bay Expedition, p. 40, plate I, figs. I, 2, Annals and Mag. Nat. Hist., ser. 6, vol. I, p. 255.

Nausithoe marginata, METSCHNIKOFF, 1886, Embryologische Studien an Medusen, Wien, p. 23 (egg); p. 37 (segmentation); p. 66 (formation of entoderm); taf. 10, fign. 1-22.

LARVAL STAGE:

Nausithoe punctata=*Spongicola fslularis = Stephanoscyphus mirabilis, LOBIANCO, S., AND MAYER, P., 1890, Zool. Anzeiger,

Jahrg. 13, p. 687.

Spongicola fstularis, SCHULZE, F. E., 1877, Archiv. fur Mikroscop. Anat., Bd. 13, p. 795, taf. 45-47 (larval stage). Stfphanoscyphus mirabilis, ALLMAN, 1874, Nature, vol. 10, 251; Annals and Mag. Nat. Hist., ser. 4, vol. 14, p. 237. Parasitic scyphostoma upon Esperia, KOWALEVSKY, A., 1873, Mem. Imperial Soc. Lovers of Natural History, Moscow, vol. 10, part 2, p. 7 (Russian).

Adult medusa. — The umbrella is discoidal, flatter than a hemisphere, quite thick, and 9 to 15 mm. wide. Central disk of exumbrella thick, raised, and lenticular with a finely punctate surface, not quite half as wide as the medusa itself and separated from the peripheral zone ot pedalia by an annular furrow. This outer zone of pedalia is composed of 16 radial thicken- ings, 8 in the radii of the tentacles and 8 in the

352-

353-

FIG. 352. — Nausithoe punctata, from life, by the author, at Naples Zoological Station, Jan. 15, 1908. FIG. 353. — "Nausicaa phtzacum," after Haeckel, in Das Syst. der Medusen.

radii of the sense-organs. They thus alternate in position with the 16 marginal lappets and are separated by deep radial clefts in the mid-axial radii of the lappets (fig. 5, plate 60). The 8 tentacles are adradial and arise from deep clefts between the lappets. The bases of these tentacles are set in thick, socket-like pedalia and arise from the subumbrella side ot the bell. The tentacles are about three-fourths as long as bell-diameter. The entodermal core of each tentacle is solid and composed of highly vacuolated cells. There are 8 marginal sense- organs, 4 radial and 4 interradial; these sense-organs are set at the bottom of 8 clefts between the lappets, but the clefts of the sense-organs are not quite as deep as those of the tentacles. The Hertwigs (1878, fig. 2, plate 9) and Claus (1883, fig. 47, plate 7) have shown that each sense-organ contains a distal entodermal mass of cystalline concretions, and a ventral proxi- mal, ectodermal eye provided with lens, retina, and nerve-fibers. The 16 marginal lappets are long, flexible, and spatula-shaped. The mouth is a simple, cruciform opening at center of

COKONATiE — NAUSITHOK.

55.3

subumbrella; the 4 lips are without prominent oral appendages or palps. The central stomach is connected with a wide annular sinus in the disk by means ot 4 wide, perradial ostia, alternating with which there are 4 short interradial septa (see Claus, 1883, p. 27, tat. 7, fig. 48). The broad ring-sinus is interrupted near the bell-margin In i'> septa in the radii ot the mid- axial lines ot the lappets. These sepia are not complete. howe\er, but lease a marginal ring-canal. Thus the 16 peripheral stomach-pouches are in the ladii ot the sense-organs and tentacles, and are joined by the marginal ring-canal in the axial line ot each lappet.

Four groups ot simple, unbranched, gastric cirri are upon the interradial septa ot the central stomach and project centnpetally inward into the central stomach; altogether there are about 28 gastric cirri, about 7 in each group. The 8 adradial gonads occur in the 8 ten- tacular radii and are upon the floor ot the subumbrella in the /.one ot the wide, inner ring- sinus ot the bell. Each gonad is large and globular and consists ot a pocket-like told ot the entoderm of the subumbrella (see Claus, 1883, p. 31). A zone ot well-developed circular muscle-fibers is on the subumbrella between, and centrifugal to, the gonads. Centripetal to this, powerful strands ot" radiating muscle-fibers extend outward to the tentacles and mar- ginal lappets; also, 8 poorly developed strands of radiating muscles extend outward in radial and interradial positions from the base ot the oesophagus to the zone ot circular muscles. The color ot this medusa is quite variable. The gelatinous substance ot the bell is usually translucent-milky, greenish, or light brownish. The gonads are brownish or red or, in the case ot the males, bright yellow. Rosin-colored spots m the ectoderm ot the exumbrella, especially upon the lappets, are due to clusters of small crystals (see Claus, 1883. fig. 44, taf. 6).

A young ephyra of this species was found by us near Flamingo Key, Bahama Islands, February 9, 1893. It was 2 mm. in diameter, and there were as yet no marginal tentacles

and only 4 gastric cirri A slightly older ephyra has been figured by Claus, 1883, fig. 48, taf. 7.

This medusa is a surface form, and is common in the Med- iterranean, Atlantic, Pacific, and Indian Oceans, and in all trop- ical or warm seas. Nausithoe polaris (Naupkanta polaris Fewkes) from the Arctic Ocean, appears to be identical with N. punctata, and if this be true Vanhoffen is right in stating that Nausithoe punctata is found in all oceans. It is abundant in summer at Tortugas, Florida, and in the Bahamas, hut has not been found on the Atlantic coast ot the United States north of the Carolinas. Vanhoffen, 1906, describes a specimen 12 mm. wide from N. lat. 59° 39', W. long. 8° 49'.

Ilamann, 1883, studied the development of the ephyra of this species and finds that the gonads first appear as 4 inter- radial entodermal swellings in the subumbrella wall of the

stomach, at a time when the ephyra has but one gastral filament in each interradius. Later the 4 original gonads divide and migrate so as to become 8 in the adradii of the subumbrella wall of the stomach. The genital products oiiginate in the entoderm and migrate into a gelat- inous space between two la\eis ot entoderm. The spermaries appear as a series of follicles in this space.

According to Metschnikoff, i8So, who has studied the early development of Naiisitlni,- "mar<;iniitii" I which is apparently identical with Y. f>iin, tnl.i I the egg is citron-yellow, 0.23 mm. in diameter, and is laid in mid-day in December; segmentation is total but somewhat unequal, the cells of the vegetative pole being hum St. \ wide, central, cleavage cavity is formed and the gastrula results from imagination at the hinder end of the lat\a. The blastopore then closes over and the entoderm is entirely inclosed by a layer of ciliated ectoderm, and the tree-swimming planula is thus formed.

The remarkable scyphostoma larva of Nausithoe punctata bears a striking superficial resemblance to a hydroid and it lives commensal within sponges such as Subnit, \c, .Uyv/7/rt, Rcneira, Esperia, etc. It is especially abundant at Trieste and Naples. This hydroid-like larva forms a branching tree-like growth within the bod\ of the sponge, the polvp-mouths and their tentacles projecting out of the oscula of the sponge. The branching, tree-like stock ot the larva is covered with an irregularly annulated, chitinous perisarc, which terminates at a short distance below the zone of tentacles of each polypite. The mouth of the polypite

FIG. 354. — " \aupltanla'' albalrossi, .lit. r M.i.r .in \lrm.\lus.Comp. Zoology at Harvard Collr^c.

556

MEDUSAE OF THE WORLD.

is at the extremity of a short, blunt-conical hypostome, which is surrounded by an annulus of about 40 solid filiform tentacles. 4 longitudinal partitions lined by entoderm extend throughout the cavity of the stem. These do not meet in the center, but form only partial septa, comparable with the mesenterial partitions of other scyphostomae of Scyphomedusze. There is no marginal ring-canal. There are external, longitudinal and internal (meso- dermal) circular muscles. The polypites are translucent-white.

Lobianco and Paul Mayer, 1890, found that ephyrae of Nausithoe arise by strobilization from this larva. The young ephyra has only 4 gastric filaments and no tentacles. Kowal- evski, 1873, also observed the giving off of the ephyrae, but did not determine that they were Nausithoe.

It is not surprising that this peculiar larva should have received various names: Allman calls it Stephanoscyphus mirabilis; F. E. Schulze describes it in detail under the name Spotig- icola fstularis; but its true nature was discovered by Lobianco and Paul Mayer, 1890.

Haeckel's Nausicaa phtsacum from Corfu, Mediterranean, may be identical with N. punctata, but the 8 gonads tend to be grouped in 4 interradial pairs, forming a broken crescent in each interradius, with a wide separation between the outwardly directed horns of each

crescent. It may have been described from an abnormal or young specimen of N. punctata (See Haeckel, 1880, Sit- zungsber. Jena. Gesell. fur Med. und Natur., Jahrg. 1880, Feb. 20.)

Nausithoe clausi Vanhoffen.

Nausithoe clausi, VANHOFFEN, 1892, Ergeb. der Plank- ton Expedition, Bd. 2, K. d., p. 14, taf. 4, fign. I, 2.

Disk about 9 mm. wide; central lens-shaped dome of exumbrella flat, smooth, unpitted, and without radial fur- rows; 5 mm. wide, 16 well-developed marginal pedalia. Medusa 3 times as wide as high. 1 6 very blunt, 3-cornered marginal lappets, three times as wide as long and hardly one-ninth as long as bell-radius. 8 adradial tentacles with well-developed, conical bases. Tentacles as long as bell-radius. 8 marginal sense- organs alternating with tentacles. 8 gonads in the tentacular radii, very small, spherical, only 1.3 as wide as the pedalia. Ring-muscle of subumbrella one-third as wide as bell- radius. Numerous, small, simple gastric cirri arising in a linear row in each interradius. Color (?)

Pacific Ocean east of the Caroline Islands. A single specimen appears to be AT. punctata with poorly developed marginal-lappets and small gonads.

Nausithoe challenged Vanhoffen.

Nauphanta challenger!, HAECKEL, 1880, Syst. der Medusen, p. 487; 1881, Report Deep-sea Medus.T, Challenger Exped., Zool.,

vol. 4, p. 103, plates 27, 28, 20 figs. Nausithoe challenger!, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Exped. Valdivia, Bd. 3, Lfg. I, pp. 28, 31.

Bell 12 mm. wide. Central lens of exumbrella separated by a deep annular furrow from zone of pedalia. Somewhat less in diameter than bell-radius, its margin cleft by 16 radiating furrows which do not extend to center of exumbrella. Marginal zone of pedalia well developed, the 8 ocular being narrower than the 8 tentacular. Tapering tentacles somewhat longer than bell-radius. The 8 large gonads are twice as long as wide and are elongated outwardly. They are somewhat wider than the intervals between them. 4 interradial clusters of simple gastric cirri which arise at equal spaces in a single row in each cluster and are not grouped into brushes as in N. albatrossi. Each cluster has about 24 cirri.

FIG. 355. — Nausilhoe rubra, after Vanhoffen, in I'aldtvia Expedition.

CORONATE — NAUSITHOE, LINUCHK. 557

Found near the island of Tristan d'Acunha, South Atlantic, at a depth of 1,425 fathoms, in an open net, on March 16, 1876.

Nausithoe' albatrossii Vanhbffen.

Nauphanta albatrosii, MAAS, 1897, Mom. Mus. Comp. Zool. at Harvard College, vol. 23, p. 83, taf. 14, fign. 1-3. Nausilhae albairissi, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsec Expedition, Bd. 3, Lfg. I, pp. 28, 30.

Disk 35 to 40 mm. wide, 35 mm. high. The marginal lappets are narrow and elongate with nearly parallel sides and rounded ends; not heart-shaped, as in Xausitlioe challengeri or N. vfttoris pisani ( = N. punctata). Central disk smooth and without a notched margin, such as is seen in N. challengt-ri. Stomach, especially the lips, much shorter than in either N . , hal- lengeri or N. vettoris pisani. 8 gonads, elongate, oval, bladder-like organs. The gastric fila- ments arise in a row in each interradius, each row being composed ot about 4 clusters, of 5 filaments each. All 5 filaments of each cluster arise close together, and \virh wide, free intervals between the groups. This species is remarkable tor its large size.

Gulf of Panama, Pacific coast of Central America.

Nausithoe rubra Vanhoffen.

Nausilhoe rubra, VANHOFFEN, 1902, Wissen. Erp'h. deutsch. Tirfsee Expedition, Bd. -\, Lfg. i, p. 30, taf. I, fign. 4, 5. — BK.I i.uu, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 36, plate 12, fig. (>.

Bell 15 mm. in diameter. With large pits over the exumbrella surface of the central disk. Simple gastral filaments arise separately, not in clusters. 8 large gonads. 16 short, pointed, marginal lappets. 8 tentacles longer than the bell-radius. Tentacles and bell red- purple, stomach blue. Indian and South Atlantic Oceans. It appears to be distinguished from N. picta by its deep color and large pits over the exumbrella surface of the central disk; moreover, according to Bigelow, 1909, the rhopalia in A*. nil>r<i lack ocelli, while there is a ventral ocellus in N. punctata. The septal nodes of N. rubra are broadly triangular and the 4 perradial gastric ostia are narrow. The marginal canal-system is as in Ar. punctata.

Nausithoe "picta" Agassiz and Mayer =N. punctata (?)

Xaufithoe pi<ta, AGASSIZ, A., and MAYER, 1902, Mem. Museum Comparative Zool. at Harvard College, vol. 26, p. 154, plate 7, fig. 33. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. II, p. 19, taf. i, fign. 5-8.

Bell 15 to 22 mm. wide, somewhat flatter than a hemisphere. Coronal furrow of exum- brella well-developed, central disk of exumbrella smooth-edged. 16 marginal lappets, wide and pointed. 8 tapering adradial tentacles, with wide bases, are somewhat snorter than bell-radius. 8 marginal sense-organs, radial and interradial in position with reference to the lips. 8 large, egg-shaped or oval gonads project horn middle zone ot subumbrella in the tentacular radii. Mouth cruciform, the lips being in the radii of 4 of the marginal sense- organs. 4 clusters of gastric cirri in the interradii, each cluster consisting of about 12 cirri.

The gonads are chocolate-brown to carmine and the gastric cirri are blue. The ocelli of the 8 sense-organs are dark-brown.

This medusa was found by the Albatross in the Paumotos Islands, South Pacific, in September, 1899. Later, 29 specimens were found by the Siboga in the Malay Archipelago. Maas, 1903, describes these specimens and fortunately corrects certain serious mistakes in tin- description wrim-n by me in the account published under the names of Agassiz and Ma\er. I am inclined to regard this medusa as merely a large, highly-colored variety ot Nausithoe punctata.

Genus LINUCHE Eschscholtz, 1829.

Linucht, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 91.

Lintrgti + Liniseut + Littucht, HAFCKEI., 1880, Syst. der Mcdusen, pp. 495, 496, 498, 642.

The type species is Linuche unguiculata Eschscholtz, 1829, of the West Indian region, tropical Atlantic.

GENERIC CHARACTERS.

Ephyropsidae with 8 (4 perradial, 4 interradial) rhopalia. 8 adradial tentacles. 16 lappets. 8 gonads grouped in 4 pairs close to the 4 perradn. \\ ith zones of hernia-like sacs upon the floor of the subumbrella. The 16 peripheral stomach-pouches break up into branches in the lappets. A marginal ring-sinus may or may not be present.

558 MEDUS.E OF THE WORLD.

There are, I believe, but two species, L. unguiculata of the tropical Atlantic and L. aquila of the Pacific and Indian Oceans. These are closely related, but in the Atlantic form there is no marginal ring-canal, whereas this is present in the Pacific species; moreover, the subumbrella warts of the Pacific form are arranged in 2 rows and in the Atlantic medusa in 3 rows.

Linuche unguiculata Eschscholtz. Plate 59, figs, i to 10.

Medusa unguiculata, SCHWARTZ, 1788, Neue Abhaiull. Schwed. Acad. Deutsche Uebers., 1789, p. 195, taf. 6, fig. l. — LINNE

(GMELIN), 1788, Syst. Nature, tomus i, pas. 6, p. 3159.

Pelagia unguicalatat PERON ET LESSUER, 1809, Annal du Museum Hist. Nat., Paris, tome 14, p. 349. Linuche utiguitulata, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 91. — BLAINVILLE, 1834-1836, Manuel d' Actinologie, p. 289, planchc

37, figs. i-ic. Liuerges tnercurius + L. pegasus + Liniscus ornithopterus (?) + L. sandtdoptcrus (?) + L. c\atnapterus + Linuche unguiculata +

L. vesiculata, HAECKEL, E., 1880, Syst. der Medusen, pp. 491;, 497, 498, 499, taf. 29, fifin. 4-6. Linerges mercurial, FEWKES, 1882, Bull. Mus. Comp. Zool. at Harvard College, vol. 9, p. 251), plate 2, figs. 3-5; plate 3, figs. 4-8,

!l, 13; plate 4, figs. 3-22; 1886, Report Commiss. Fish and Fisheries for 1884, p. 950. — ACASSIZ, A., 1888, Bull. Mus.

Comp. Zool. at Harvard College, vol. 14, p. 186, fig. 93. — MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard College, vol.

37, p. 68. — CONKLIN, 1906, Year Book of Carnegie Institution of Washington, No. 4, p. 1 15; 1908, Papers from Tortugas

Laboratory Carnegie Institution of Washington, vol. z, p. 153, 8 plates (development).

Bell about 13 mm. high and 16 mm. wide. Lenticular apex flat and horizontal, separated from the vertical sides by a distinct but shallow annular furrow. Occasionally a few irregu- larly arranged, radiating clefts are found in the margin of the lenticular apex of the bell, but this is usually plain. Sides of bell composed of 16 vertical pedalia, similar each to each, and separated one from another by 16 clefts in the radii of the mid-axial lines of the lappets. Thus the pedalia are in the radii of the tentacles and rhopaha and alternate with the lappets (plate 59, fig. 2).

The 1 6 lappets are bluntly oval with rounded edges and are all inclined inward at an angle such that when one observes the medusa by looking down upon the aboral end of the bell the animal rotates with the hands of the watch as it swims through the water, upon each contraction of its margin. The lappets being inclined as are the vanes of a wind-mill cause this peculiar spinning on its axis as the medusa progresses rapidly along. This was discovered by Prof. E. G. Conklin in 1905. 8 small, simple, marginal sense-organs, perradial and inter- radial in position, arise from clefts between the lappets and are not protected by covering scales. The entoderm of each rhopalium contains a spherical mass of concretions. No ocelli. The 8 adradial tentacles are small, neither very flexible nor contractile, and only about 1.5 times as long as lappets.

The 8 (4 double) gonads form 4 cleft crescents on both sides of the perradial lines of the subumbrella, the cleft being in the perradius itself and the horns of the crescents extending outward toward the margin of the bell. These gonads begin to develop as 8 separate sacs diverging outwardly on either side of the 4 perradii when the ephyra is about 5 mm. in diameter. The subumbrella sacs are not male gonads as was conjectured by Haeckel, and the medusa is not hermaphroditic, the sexes being separate.

The proboscis is urn-shaped, 4-sided, and with 4 slightly recurved lips with their perradial angles truncated so as to present a nearly octangular appearance when viewed upon looking into the bell-cavity. The mouth does not extend to level of bell-margin, but is usually at about two-thirds the distance down from the inner apex of the bell-cavity. There are 4 cres- centic interradial rows of simple unbranched gastric cirri, about 15 to 20 in each row at the interradial septal nodes. Beyond these, and connected with the central stomach by 4 perradial ostia, is the broad bell-sinus, which in turn gives rise to 16 radiating pouches in the radii of the sense-organs and tentacles. The edges of these pouches break up into numerous, ragged-edged branches in the lappets, but I am unable to find any marginal ring-canal, for although I have often injected the lappet-pouches with air, carmine, or other stains, each pouch is evidently completely separated from the two adjacent to it. This appears the more remarkable from the fact that Maas has found a marginal ring-canal in the Pacific species; a fact which I am enabled to confirm in specimens from the Philippine Islands, and Claus, Vanhoffen and Bige- low have demonstrated that such a structure exists in other Ephyropsidae.

Projecting from the floor of the subumbrella into the bell-cavity are 48 hollow sac-like or wart-shaped protuberances which arise from the radial stomach-pouches and are arranged

PLATE 59. Figures I to 10 are of Linuche unguiculata; figure 1 1 is of Linuche aquila.

Fig. I. Side view of mature medusa. Key West, Florida, June I, 1897. Fig. 2. Side view of bell of mature medusa showing sculpturing of the exum-

brella. Tortugas, Florida, May 12, 1906. Fig. 3. Oral view of an ephyra 2 mm. in diameter. Nassau Harbor, Bahamas,

March 10, 1893.

Fig. 4. Marginal sense-organ of the ephyra shown in figure 3. Fig. 5. Oral view of an ephyra 7 mm. in diameter, showing the 4 pairs of

gonads beginning to develop on both sides of each perradius, and

masses of brown cells. Ragged Islands, Bahamas, April 5, 1907. Fig. 6. The mouth-parts of the ephyra shown in figure 5. Showing gonads

and gastric cirri. Fig. 7. Oral view of mature medusa, showing the subumbrella saccules.

Tortugas, Florida, May 8, 1907. Fig. 8. Oral view of a mature medusa, showing the 16 radial pouches of the

central stomach. There is no marginal ring-canal. Fig. 9. Marginal sense-organ of a mature medusa. Fig. 10. Side view of an ephyra 3 mm. in diameter, showing the beginning of

the tentacles. Nassau Harbor, Bahamas, March 14, 1893. Fig. II. Linuche aquila, Wailangilala Atoll, Fiji Islands, South Pacific,

November 20, 1897.

Drawn from life, by the author.

MA •

PLATE 59

\

-

CORONATE — LINUCHE. 559

in 3 zones (text-fig. 356A). The 2 inner rows are each composed of 8 large perradial and interradial saccules which lie between the gonads, the 8 innermost saccules being partially cleft and bean-shaped (plate 59, fig. 7); a third row of 32 smaller saccules, 2 for each lappet- pouch, lies at the level of the outer ends of the horns of the crescentic gonads. In the sub- umbrella we find a broad, unitary, marginal area of ring-muscles, and centripetal to this are more or less isolated strands of radial muscle-fibers.

The entoderm of the gonads, ot the wan-like saccules, and of numerous, separated, more or less polygonal areas of digestive cells in the gastric pouches is brown. 8 rows of dark-brown spots extend longitudinally down the inner surface of the lips.

Vast numbers of the ephyrae of this medusa appear among the Bahama Islands and West Indian region in February and March, and become mature from April until early June, usually disappearing at or about the middle of May. I have seen hundreds of such swarms, all composed of but one species. I have never seen any of the so-called "species" described by Haeckel from the West Indian region, and it appears to me that he has constituted species out of preserved material displaying various well-known characteristics ot abnormal con- traction and in various stages of growth. In tact I have seen Haeckel's "species" only in medusae which I have myself preserved. They appear not to exist except in alcohol.

In the Bahama-Florida region in spring these medusae form swarms, miles in extent, filling the water with myriads of brown thimbles, all actively spinning clockwise as they progress through the water.

Conklin, 1908, has studied the habits and early development of Linudie unguiculata. When mature the medusae rise in vast swarms to the surface and the eggs are discharged and fertilized at 8 p. m. The female gonads are slat}' or blue-gray in color while those of the male are brown. When the gonads have been emptied the medusas sink down to the bottom and die. Each egg is closely invested by a very thin transparent membrane which persists to the gastrula stage. The eggs are laid near the surface but gradually sink downward. The newly laid egg is 0.24 mm. in diameter. It consists of a peripheral layer of clear protoplasm, an intermediate layer of densely packed yolk spherules, and a central sphere composed appar- ently of dissolved yolk. The peripheral layer becomes the peripheral layer of the blastula and gastrula, and gives rise to the cilia ot the ectoderm. The intermediate "shell" ot closely crowded yolk spherules constitutes the principal part of all of the cells of the gastrula and blastula, while the central mass of dissolved yolk is poured into the cleavage cavity and probably serves as a source of nourishment for the surrounding cells.

Two polar bodies are formed. The first two cleavages are meridional and cut downward from the animal (polar body) pole to the vegetative pole, and the third cleavage is equatorial. Up to the 64-cell state the divisions are wholly mitotic. Cleavage is total and practically equal. When the embryo consists of about 1,000 cells protoplasmic processes appear over the entire periphery, and these push off the egg membrane and form the vibratile cilia. Gastrulation usually takes place by invagination of the small, rounded cells ot the vegetative pole ot the embryo; but sometimes there is a unipolar mgression of cells at the vegetative pole and no invagination. The blastopore closes so that the entoderm becomes entirely incased within the ectoderm, and the larva elongates and becomes a free-swimming planula.

Isolated blastomeres, at least as late as the 4-cell stage, may give rise to apparently normal free-swimming larvae.

The center ot the egg is more nearly fluid than the peripheral layers, and this fact favors the cutting inward of the cleavage furrow from the animal pole to the vegetative during the first two divisions, and the unilateral constriction in the third (equatorial) division.

When the ephyra is 1.5 mm. in diameter, it has 16 lappets and 8 sense-organs, but neither tentacles nor gonads. 4 gastric cirri, one in each interradial side of stomach. Disk very flat, brown in color (fig. 3, plate 59). When 3 mm. wide the tentacles begin to develop, and the gonads appear when the medusa is about 5 mm. wide. The polygonal areas of pigmented digestive cells then develop in an inner ring of 16 large areas centrifugal to the gonads, and still farther out an outer annulus of 32 areas. There are also irregularly shaped and arranged areas of brown cells in the lappets (plate 59, fig. 5). The subumbrella saccules do not develop until later.

560 MEDUSA OF THE WORLD.

Linuche aquila. Plate 59, fig. n.

Liner ges aquila, HAECKEL, 1880, Syst. der Medusen, p. 496. — GOETTE, 1886, Sitzungsber., Akad. Wissen., Berlin, Jahrg., p. 833. — AGASSIZ, and MAYER, 1899, Bull. Museum Comp. Zool. at Harvard College, vol. 32, p. 170, plate 10, figs. 33, 34; 1902, Mem. Ibid., vol. 26, p. 156.

(?) Linerges draco, HAECKEL, loc. cit., p. 496.

Linerges draco (young medusa), MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, p. 24, taf. I, fign. I, 2.

This form is widely distributed over the tropical Pacific and is closely related to the tropical Atlantic L. unguiculata, with which it is identical in form and dimensions, being about 13 mm. high and 16 mm. wide. It has 48 wart-like protuberances upon the subumbrella arranged in 2 rows instead of in 3 as in the Atlantic medusa. 8 of the subumbrella sacs in L. aquila alternate with the gonads and 8 arise from the sides of the gonads themselves. Thus in the Pacific medusa we have two zones of protuberances, an inner zone of 16 large sacs, and an outer of 32 small subumbrella saccules. The 16 large sacs lie in the mid-regions of the gonads, while the 32 small saccules lie at the zone of the outer ends of the gonads. The areas of brown cells are developed only centrifugal to the zone of gonads in the Atlantic, while they occur between the gonads as well as beyond them in the Pacific medusa. A marginal ring-canal is present.

FIG. 356. — A, arrangement of subumbrella warts in Linuche unguiculata of the tropical Atlantic. B, arrangement of subumbrella warts of Linuche aquila of the tropical Pacific. C, enlarged view of central part of subumbrella of Linuche aquila, showing lips, gonads, and saccules.

Vast swarms of these medusae are found among the atolls of the Fiji and Paumotos Islands, and they extend westward to the coast of Africa. They abound in the spring months, in Fiji in December and at Singapore in April. I have studied a large collection of these medusae taken in the Philippine Islands at Mactau, near Sibu, on April 6, 1908, by the U. S. Bureau of Fisheries steamer Albatross. All were mature.

There appear to be no valid distinctions in Haeckel's descriptions between L. aqutla and his " L. draco" the differences being such as one would expect to find in two contracted preserved specimens. Haeckel's Linantha lunulata (Syst. der Medusen, p. 494, taf. 29, fign. i to 3) is possibly the young of L. aquila. It is said to have 4 interradial horse-shoe-shaped gonads, but in all known species of Linuche the gonads are more nearly perradial than inter- radial. It is evidently an immature form, being only 10 mm. wide, and has no subumbrella saccules; indeed, the figure itself shows its ephyra-like condition. It comes from the Gala- pagos Islands, off the Pacific coast of South America.

CORONAT^E — ATOLLA. 561

Family COLLASPIDjE Haeckel, 1880.

Collaspidx, HAF.CKF.L, 1880, Syst. dcr Mcdusen, p. 488. — VANHUFFKN, 1906, Nordischcs Plankton, \r. 11, p. 44. Atoll iil.r, Hi i. now, H. H., 1909, Mi-m. Mus. Comp. Zool. at Harvard College, vol. 37, pp. 21, 37.

FAMILY CHARACTERS.

Coronatae with numerous (more than 8) marginal sense-organs which alternate with an equal number of tentacles. Marginal lappets twice as numerous as the tentacles.

Atolla is the only known genus.

Genus ATOLLA Haeckel, 1880, sensu Fewkes.

Alolla+Collmftis, ll\n KM , 1880, Syst. der Medusen, p. 488; 1 88 1 , Deep-Sea M III c, < ::,illrngrr Report. Zool., vol. 4. p. I I I .

Atolla, I > \\kts, iS86, Report Commiss. Fish and Fisheries U. S. A. for 1884, p. 934; ( r) Ephyroidcs, 1885; Ibid, for 1883, p. 597; and 1886, p. 948; 1889, p. 53*. — VAMIUI i FN, 1891, Ergcb. der Plankton Expedition, Bd. z, K. d., p. 16; 1902, Wissen. Krtjeb. ilfnt M h. 'In f sec Expedition, DamptVr I'uIJi: i,i, iiu. ;. Lfg. I . p. 5; 1906, Nordisches Plankton, Nr. 1 1 , p. 44.— MAAS, 1897, Mem. Mus. C'oinp. /mil. at Harvard College, vol. 2;, No. i. pp. 78, 79; 1899, Bull. Soc. Zool. dc France, p. 165; 1904, Result Camp. Sci. Prince dc Monaco, fasc. 28, p. 48; 1903, Scyphomedusen dcr Siboga Elpcdition, Monog. u, p. 14; 1907, Ergeb. und Fortschrittc der Zool., Bd. I, p. 195. — BROWNE, 1908, Trans. Roy. Soc. Edinburgh, vol. 46, p. 240.— BIOLLOW, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 37.

GENERIC CHARACTERS.

Coronats with numerous (9 or more) tentacles and equally numerous marginal sense- organs. Twice as many marginal lappets as sense-organs. 8 adradial gonads and 4 inter- radial subgenital osiia. 4 lips. The tentacles and marginal sense-organs alternate regularly, but the insertions of the tentacles and their pedalia are higher up on the exumbrella than are the insertions of the pedalia of the sense-organs.

The type species is tvyvillet Haeckel.

Haeckel distinguished "A toll n" with 8 gonads grouped in 4 pairs and "Collaspis" with 8 separate, equally spaced gonads. As was first shown by Fewkes, 1886, both of these con- ditions may exist upon one and the same medusa, some ot the gonads being paired, others separated by equal spaces. The name "C alias f is " must therefore be dropped, being equiva- lent to /holla.

The medusae of this genus are deep-sea forms and are inhabitants of all oceans, and large numbers of them have been taken in open nets dragged at 350 to 2,500 fathoms. A tew specimens have also been found upon the surface, but this is unusual. They are often brought up from depths of about loo fathoms where the ocean is more than 2,000 fathoms deep.

In the sculpturing of the exumbrella, the structure of the tentacles, the general features of the anatomy of the gastrovascular system, and in the arrangement of the muscular system, these medusae are strikingly similar to Periphylla but differ in the absence ot tunnel cavities in the Boot ot the subumbrella and in the flat, discoidal shape ot the bell. The central Stomach- cavity is thus less complex, but not essentially different from that of Pfriphylla.

The details of the structure of gastrovascular system, sense-organs, gonads, etc., are given in the description ot .7. bairdii,

Ephyroides rot af or mis Fewkes, 1886 (Report U. S. Fish Commission for 1884, p. 949), may be closely related to Atolla. The 16 to 32, or more, pedalia are separated by wide intervals instead of In narmw clefts, as in Atolla. Several specimens are mentioned by Fewkes as having been dredged from depths of 389 to 1,555 fathoms in the Gulf Stream off the coast ot the United States, hut were not sufficiently well preserved to admit of description.

VanhofFen, 1902, discovered in Atolla, a system of excretory openings which consists of 8 pores, 2 in each principal radius near the perradial angles of the stomach and centripetal to the zone of the gonads. with which this system has no connection. The position of these openings is marked by 8 oval spots upon the floor of the subumbrella. The closely allied Ephyropsidce have numerous openings on the subumbrella at the place of connection between the tentacular canals and the ring-canal, but these have not been observed in Atolla.

\ .mhottcn (1902), Maas (1904.) and Bigelow (1909), have given the best detailed descrip- tion of the genus Atolla. The development is unkno\\n.

562

MEDUSA OF THE WORLD.

Bigelow concludes that the sculpturing of the central lens of the exumbrella, the presence or absence of warts, etc., constitute the best criteria for the separation of species. The furrows ot the central lens are, when present, always one less in number than the tentacles. Bigelow doubts the existence of A . alexanJn and finds slight furrows on the central disk of the specimens which I described from Hawaii as A. alexandri. He therefore merges "A. alexandri" with A. wyvillei.

A study of the large number of specimens of Atolla in the National Museum at Washington convinces me that A. bairdn and A. wyvillei are very closely related if not mere individual variations of one and the same species. In some specimens the annular ridge in the outer side of the ring-furrow is so narrow and indistinctly separated from the marginal zone of pedalia that one hesitates to decide whether to consider it to be present or absent. Moreover the margin of the central lens in all Atollas is apt to be more or less notched with faint sinuosities in its outline, and thus A. bairdn and A. wyvillei may be only varieties of one and the same species.

8 so-called species of Atolla have been described, but I believe only three can be distin- guished upon non-intergrading characters. These are:

A. bairdii Fewkes, with an annular ridge within the ring-furrow between the central lens and

the marginal zone of pedalia. Exumbrella surface of lappets smooth. A. valdivia: and

A. gigantea are probably identical with A. bairdn. A . chum Vanhbffen has the exumbrella surface of lappets besprinkled with papillae, very wide

central lens, and an annular ridge in ring-furrow. A.u'vvillet Haeckel, with margin of central lens notched with radial furrows; no annular ridge

in the ring-furrow. This is probably identical with A. achillis and A. verrillii.

A synopsis of the distinctive characters ot the forms is presented in the following table:

Synopsis of the So-called Species of Atolla.

	A. bairdii.*	A. valdivia?.*	A. gigantea.*	A. chuni.	A. wyvillei= A. achillis.j'	A. verrillii.-f-
Width of bell in	12 to 72	132	150	27 to 50	58 to 66	95
mm.
Width of central	5 to 40, usually	Half as wide as	70	22.5 to 38	About 29 to 33.	About 50.
lens.	more than half	medusa.
	as wide as me-
	dusa.
Annular ridge on	Smooth with	As in A. bairdii.	Notched in outer	Hidden within	Hidden within	Hidden within
the outer side of	even margin.		margin. Con-	the ring-furrow.	the ring-furrow.	ring-furrow.
the ring furrow.			tracted ?
Radical furrows	None; but the	As in A. bairdii.	As in A. bairdii.	Notched with 23	Notched with 1 5	Notched with
of central lens.	margin is in-			shallow radial	to 31 radial	13 to 27
	dented with 17			furrows.	cleftsor grooves.	shallow radial
	to 23 notches.					clefts.
Number of ten-	1 8 to 24	20 to 29	?	24 ±	16 to 32	14 to 28
tacles.
Exumbrella sur-	Smooth.	Smooth.	Smooth.	Covered with	Smooth.	Smooth.
face of lappet				papilla?.
zone.
Where found.	North Atlantic.	Indian Ocean.	Gulf of Panama.	Cape of Good	Antarctic.	Atlantic, Indian,
			Panama.	Hope, Africa.	Tropical Pacific.	and Pacific
						Oceans.

*These are probably all A. bairdii.

•(•These are probably A. wyvillei.

To a great extent the conditions exhibited by these so-called species of Atolla intergrade. For example we can draw no sharp line ot distinction throughout the series between a smooth, central lens with faint notches in its margin and as is seen in A. bairdii, and a lens deeply furrowed by radiating valleys as in A. wyvillei. Similarly the wide, annular ridge, which pro- jects prominently on the outer side of the ring-furrow in A. bairdii grades insensibly to the condition seen in A . wyvillei wherein the ridge is so narrow that it is quite hidden by the ring- furrow which over-arcbes it. With the exception of A. chuni, which stands apart, all of the others may be mere local races or varieties of one variable species, A. wyvillei.

CORONATE — ATOLLA.

568

Atolla bairdii Fewkes.

Atolla bairdii, FEWKES, J. \V., 1886, Report Commiss. Fish and Fisheries t'. S. A. for 1884, p. 936, plates 1-3, 4 figs.; 1888, American Journ. Sci., ser. 3, vol. 35, p. 172; Ann. Mag. Nat. Hist., ser. 6, vol. i, p. 253; 1889, Report Commiss. Fish and Fisheries U. S. A. for 1886, p. 530.— AGASSIZ, A., 1888, Bull. Mus. Comp. Zool. at Harvard College, vol. i <;, p. 132, fig. 427.— VANHO'FFEN, 1892, Ergeb. der Plankton Expedition, Bd. 2, K. d., p. 16, taf. 4, fign. 3-9; 1902, Wissen. Ergcb. deutsch. Tiefsee Exped., DamptVr l\ilJn i,i, Bd. 3, I.ief. i, p. 9; 1906, Nordischcs Plankton, Nr. 1 1, p. 44, fign. 4, 5. — MAAS, 1897, Mem. Mus. Comp. Zool. at Harvard College, vol. 23, p. 79; 1904, Result. Camp. Sci. Prince de Monaco, fasc.28,p.49, planche 4, figs. 29-34: planche 5, figs. 38-43. — BROWN- F, luo6,Trans. Linnean Soc. London, scr. 2, Zool., vol. 10, p. 179.

The medusa is 30 to 144 mm. in diameter, disk quite flat. Central lenticular part ot exumbrella somewhat more than half as wide as entire medusa. It is flat aborally and sur- rounded by a recurved rim, the periphery of which displays about 20 to 22 slight notches, which are one less numerous than the tentacular pedalia in whose radii thev tend to lie. Central lens separated from peripheral part of exumbrella by a deep, broad, annular groove, slightly over-arched by the recurved rim of the central lens itself. The peripheral zone ot the exum- brella includes all that part of bell which lies centrifugal from the annular groove. It may in turn be divided into 4 zones: (i) The innermost zone is a simple, smooth-surfaced, annular ridge bounded on the inner side by the deep annular groove and on the outer by a very slight, reddish-colored groove which separates it from (2), the zone of the tentacular pedalia. There

FIG. 357. — Atolla bairjii, after Maas in Result. Camp. Sci. Albert icr Prince de Monaco. A, and B, side views of the medusa; C, marginal canal-system and ring-muscle (cut across).

are about 18 to 24, usually 22, pedalia, one in the radius of each tentacle. These pedalia are thick ridges separated one from another by shallow radiating furrows, which do not cut verv deeply into the gelatinous substance, so that the tentacular pedalia form a thick, continuous, gelatinous zone. Each pedalium bears a short, solid tentacle, usually carried recurved upward and provided with strong, longitudinal muscles upon its subtimbrella side.

The third zone is that of the pedalia of the sense-organs and lies immediately centrifugal to the zone of the tentacular pedalia. These pedalia ot the sense-organs alternate in position with the equally numerous, tentacular pedalia. They are lower than the tentacular pedalia and are separated from one another by deep, wide, radiating furrows which occupy the radii of the tentacles. Sense-organs very small with 2 swollen regions upon the ventral (subum- brella) side of the bulb where one finds thickened, sensor}- ectodermal epithelium. There is no ocellus and there are no pigment spots either in the ectoderm or the entoderm, but there is a terminal sac-like swelling which contains a crystalline mass of entodermal origin and which is protected by a wide, scale-like expansion on the exumbrella side of the sense- club. (See VanhofFen, 1902; Maas, 1904.)

The fourth or outermost zone of the exumbrella consists of long, slender, marginal lappets supported by the pedalia of the sense-organs, and which are twice as numerous as the latter.

564

MEDUSvE OF THE WORLD.

The center of the subumbrella is occupied by the shallow proboscis, the 4 lips of which are simple and cruciform. Surrounding the base of the proboscis is a zone in which are situated the 8 adradial gonads. The gonads vary considerably in size and shape, but normally appear to be composed of bean-shaped sectors, each genital ridge being constricted radially by one or more deep furrows (see Vanhoffen, 1892, taf. 4, fig. 4, g). 8 groups of radial-muscles lie in the floor of the subumbrella between the 8 gonads. Immediately centrifugal to the zone of the gonads lies a zone of circular muscle-fibers which is divided into separate parts by furrows which lie in the radii of the sense-organs. Beyond this zone lies the outermost ring of circular muscles developed so remarkably that it projects outward from the floor of the subumbrella as a thick annular mass, which is entire, not divided, as are the inner, circular muscles. The cavity of the central stomach communicates with a broad ring-sinus in the subumbrella by means of 4 perradially situated ostia. This ring-sinus corresponds in position to the zone of the gonads upon the subumbrella. Centrifugally it gives rise to a radiating vessel in each tentacular radius and also to an equal number of vessels to the sense-clubs. The ten- tacular vessels each give off a pair of side-branches which lead into the rhopalar vessels near the bases of the sense-clubs. At the point of origin of each tentacular vessel there is a region of fusion of the subumbrella and exumbrella walls of the gastrovascular cavity thus forming a small cathammal plate in the middle of each tentacular vessel (see fig. 359 C).

FIG. 358. — Aiolla valdivia, after Vanhoffen, in FalJivia Expedition. View of subumbrella.

The excretory system of the exumbrella has been described under the genus Atolla.

In the corners of the central stomach are 4 interradial rows of gastric cirri forming a cross with perradial axes. Altogether the gastrovascular system, the pedalia of the exumbrella, and the structure of the muscular system, with the exception of the remarkable unitary ring- muscle of Atolla, are quite alike in both Atolla and Periphylla and indicate a genetic rela- tionship between the two forms.

The gelatinous substance of the bell of Atolla bairJii is translucent and milky-blue in color. The central disk of the exumbrella is sprinkled over with rust-red colored patches which become more numerous in the region of the annular furrow, which is of a decided red- brown color. The powerful centrifugal circular-muscle band of the subumbrella is dark-red and a radial red streak extends inward on the subumbrella side from the base of each sense- organ to the band of circular muscles. Gonads and entoderm of central stomach red. The 8 adradial excretory pores near the 4 angles of the central stomach are dark-red of the hue so commonly seen in deep-sea medusae of all ports.

CORONATE — ATOLLA.

This species is widely distributed over the North Atlantic. It has often been obtained in open nets dragged at depths from goo to 2,000 fathoms, but has also been taken occasionally upon the surface, especially upon the Gulf Stream off the Carolina coast. It is a creature of the deep ocean, not found in bays or estuaries, but is evidently a deep-sea medusa that may only occasionally and under exceptional conditions come to the surface.

When young the 8 gonads are grouped in 4 interradial pairs, but in later lite they swing into adradial positions. The number of antimeres does not alter with age; but in some specimens one finds some small tentacular pedalia inserted between larger rhopalar ones. Vanhoffen records 11 specimens ranging from 5.5 to 114 mm. in diameter and with 18 to 24 tentacles. These were found by the falJti'ia in the Gult ot Guinea, west coast ot Africa.

Atolla bairdii forma valdivias Vanhbffen.

Atolla valdivia, VANHOFFEN, 1902, Wisscn. Ergeb. deutsch. Tiefsee Expedition, Dampfcr I'alJhia, Bd. 3, Lief. I, p. 13, taf. i, fig. 3; taf. 5, fig. 21 ; taf. 6, fign. 41-46; taf. 7- — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, p. 17, taf. i, fign. 3,4; taf. 3, fig. 23; taf. 12, fig. 108.

Medusa 132 mm. in diameter. Central disk only half as wide as bell, smooth, without radial furrows. 20 to 29 tentacles. The 4 interradial septal nodes of the subumhrella are wider than in the typical A. bairJii. 9 specimens were found by the I'aUivia in the Indian Ocean. Maas records 9 specimens obtained by the Siboga in the Malay Archipelago. These ranged from 12 to 82 mm. in diameter, the central disks ranging from 6 to 42 mm. in width; and the antimeres range from 20 to 29 without reference to the size of the medusa. These medusae were obtained from depths ranging from about 280 to 1,000 fathoms (see fig. 358).

This form is very closely related to A. bairdii but the central disk is only half as wide as the medusa, and the 4 septal nodes are wider than in A . bairdii.

The Albatross obtained 3 specimens of this medusa in the Philippine Islands on April 10, 1908, at dredging station No. 5202. The characters and dimensions, in mm., ot these specimens are as follows:

	Specimen A.	Specimen B.	Specimen c.
Exumbrella:	45-5 21.5 '•5 4 3 3-5 7-5 43 2.25 J' '5 7 6 M	38 19 1.25 3-5 *-75 3 5 35 3-5 20.5 '3 *-5 3-5 22	37 18.5 3-zS 3 2-S 5-75 34 2-S Z3 '4 3-5 3 *4
Subumbrclla:
General characters:

Atolla gigantea Maas = A. bairdii (?)

Atolla gigantea, MAAS, 1897, Mrin. Mils. Comp. Zool. at Harvard College, vol. 23, p. 80, taf. 12, fign. 2-4; taf. 13, fign. 7-9; taf. 14, fig. 6.

This form resembles A. valdiviee, but the outer edge of the annular ridge in the ring-furrow is notched, not simple and entire as in A . bniiJn and A . 1'nliiii'nr. Thus the central lens is half as wide as the bell, as in A . valJivite. Ring-furrow wide, and peripheral to it there is the notched, annular ridge, and beyond this is the zone of pedalia and lappets. Tentacular pedalia somewhat shorter and wider than the rhopalar pedalia. Medusa is 150 mm. wide. Num- ber of tentacles ( ?) Gulf of Panama, Pacific coast of Central America (see fig. 359).

Maas is uncertain as to whether or not the margin of the central lens is plain or notched. Radial furrows of the ridge in the ring-furrow may be due to contraction in preservative fluids.

566

MEDUS/E OF THE WORLD.

Atolla chuni Vanhoffen.

Atolla chuni, VANHOFFEN, 1902, Wissen. Ergeb. doutsch. Tiefsee Expedition, Dampfer Paldivia, Bd. 3, Lief. I, p. 12, taf. I, figs, i, 2; taf. 5, fig. 26. — BROWNE, 1908, Trans. Roy. Soc. Edinburgh, vol. 46, p. 240.

Bell 27 to 50 mm. wide, 9 to 15 mm. high. Central lenticular disk 14 to 27.5 mm. wide with 23 faint radial furrows at the margin. Annular furrow 0.5 to 1.75 mm. wide. Zone of pedalia 2.25 to 3.5 mm. wide. 24 tentacles. Species distinguished by 7 to 9 small, pearl- colored, papilla-like protuberances over the exumbrella surfaces of each marginal lappet; commonly with one papilla in the center and the others in two lateral rows. 2 specimens found by the I'alJivia off Cape of Good Hope, Africa, November 1 8, 1898; and I by the Scot- tish Antarctic Expedition, in a trawl at 1,332 fathoms, in the same region.

359

FIG. 359. — Atolla gigantea, after Maas, in Mem. Mus. of Comp. Zool. at Harvard College.

Fi<;. }6o. — Atolla chuni, after Vanhoffen in I'aldivia Expedition.

FIG. 361. — Atolla wyvillc I, 0.75 natural size, drawn by the author, from a specimen in the National Museum, Washington.

Atolla wyvillei Haeckel.

, , , ..,

Atolla alexanJri, MAAS, 1897, Mem. Museum C A U

ss acs, AECKEL, 10, oc.c., p. 49.

exanJri, MAAS, 1897, Mem. Museum Comp. Zool. at Harvard College, vol. 23, p. 81, taf. 1 1, fig. 2; taf. 14, figs. 4, 5. — GASSIZ, A., and MAYER, 1902, Mem. Museum Comp. Zool. at Harvard College, vol. 26, p. 156. — MAYER, 1906, Bull. . S. Fish Commission, vol. 23, p. 1138, plate 2, fig. 7; plate 3, figs. 10, u.

This species is characterized by the numerous, wide, radial notches or furrows in the margin of the central lens of the exumbrella. These are much wider and deeper than in A . verrillii. Exumbrella surface of lappets smooth, not beset with papillae as in A . chuni. This medusa is probably identical with Collaspis achillis Haeckel, but in the latter the furrows of the central lens are represented as deep, narrow clefts, whereas in A.iL'yvillci they are shallow notches which vary greatly in prominence in individual medusae. Moreover, in A. wyvillei the pedalia are short and broad, while in A . achillis they are long and narrow. The central lens and the pedalia are separated only by a ring-furrow and there is no prominent ridge periph- eral to the ring-furrow such as is seen in A. bairdii. The medusa becomes 73 mm. wide and there are usually about 22 to 28 tentacles. The bell is flatter than a hemisphere. Found in the Antarctic and Southern Atlantic and Pacific. The Albatross obtained it in the Philippine Islands, tropical Paci-fic.

CORONATvE — ATOLLA.

567

I am inclined to believe that A. uTcill,-i, A. verrillii, A . alexandri, and A. achillis are only varieties of one and the same species. "A. <ih-\<inJri" is a form of A . wyvillei with indistinct notches in the margin of its central lens.

A specimen was dredged In the Albatross on April 10, 1908, dredging station No. 5201, off the south end of Levi Island, Philippine Islands, from a depth of 554 fathoms. A side view is shown in fig. ^>i. There were i^ pedalia and tentacles, and 22 radial furrows in the margin of the central disk. The dimensions in millimeters are as follows:

Diameter of bell 55

Thickness of bell 26

Diameter of central lens 40

Depth of coronal furrow ;

Length of tentacular pedalia. ... 6.5 Diameter to outer edge of ring- muscle 48

\\ nlili "f tentacular pedalia 6 \Vidthofring-muscle 3

Length of pedalia of lappets 6.5 Diauictcr across zone of gonads.. 28.5

\Vi,ith of pedalia of lappets

Length of tentacles i ;

Diameter of manubrium

I .- M ;ih of manubrium 22

< ii.ti.i U 7 long in the circumferential direc- tion, 5 wide in the radial direction.

Atolla wyvillei forma verrillii Verrill.

Ata/la rrrrillii. VtRRiiL, 1885, Report I'minni- . I'i li .in. I fisheries V. S. A. for 1883. p. ^14. -KiwKis. 1885, Report Commiss. l'ih .in.! l-'i.-herie, 1 - v \.toi iXX-,. p. l'i''; ftiW., 1886, Report for 1884, p. 939, plates 4, 5, 4 figs.; /'-/</., 1889, Report for 1886, p. 530; 1888, American J.iurn. Su., MT. 3, \.il. 3;, p. 1^2; 1888, Ann. .Mag. Nat. Hist., ser. 6, vol. i, p. 253. — M*\s. I*T. Mem. Mil emu (."ON i p. /."„!. at H.ir. .u,l College, vol. 25, p. 79. • VAN MC 1 11 1 i \. 1902, Wissen. Ergeb. deutsch. Tiefsee Evped.. I'alJi-ia, Bd. 3, Lief. I, p. 10, taf. 5, fit;. 23; taf. 6, fig. 39; taf. 7; 1908, dcutsche Sudpolar Expedi- tion, Bd. 10, Zool. 2, p. 311.

This form is distinguished from the typical Atolla hnirJii and resembles A. wyvillei by the absence of a projecting annular ridge on the outer side of the ring-furrow, the numerous, fine, radial furrows of its central dome, the long, narrow pedalia of the sense-organs, and the smallness of its marginal lappets. The medusa becomes 95 mm. wide and has between 14 to 28, usually 22, tentacles and marginal sense-organs and 28 to 56 small lappets. Central lens of exumbrella wider than in ,/. Inui-iln. It is found in deep water in the Atlantic, Indian, and Pacific Oceans. Most of the specimens have been obtained in open nets dragged from depths of 373 to 2,369 fathoms; but several hare been found upon the surface. It is probably only a variety of//. wyvilLi.

Family ATORELLID^C Vanhoffen, 1902.

AtorelliJic, YANHOITKN, 1902, \Vissen. Ergeb. deutsrh. Tiefsee Expedition I'ltlili: ia, Bd. 3, I,fg. I, p. 51.— BIGELOW, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, pp. 21, 30.

FAMILY CHARACTERS.

with 6 rhopalia.

There is hut a single known genus, this being .Itor.-lla.

The relationship between the Atorelluhe and other Corona t;c is unknown; tor in the Periphyllidae, Paraphyllinidae, and Ephyopsidae there are 4 or 8 rhopalia, and in the Collaspidae a large (more than 8) but indefinite number ot these organs; and it is impossible at present to determine how the number h may have been derived in the Atoiellidx. It is probable, how- ever, that its affinities are much closer to Atolla than to the other Coronatae.

Genus ATORELLA Vanhbffen, 1902.

Aiorella, VANHOFFEN, 1902, \\ 'i^en. Ergcb. deutsch. Ticfsce Expedition, Dampfer Vald'rvia, Bd. 3, Lfg. i, p. 33. — MAAS, 1903, Scyphomedusen der Sihoga Expedition, Monog. 1 1, p. 10. — BIGELOW, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 30.

The type species is Atorella sukglobosa Vanhoffen, of Dar es Salaam, Africa, and from the Malay Archipelago.

GENERIC CHARACTERS.

Coronatae with 6 marginal sense-organs, 6 tentacles, 12 marginal lappets, and 12 pedalia. A coronal furrow is present, and the 12 pedalia alternate with the lappets. There is a poorly developed ring-muscle in the subumbrella. 4 lips, 4 interradial gonads.

51 IS

MEDUSAE OF THE WORLD.

Atorella subglobosa Vanhbffen.

Atorella subglobosa, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Valdivia, Bd. 3, Lfg. i, p. 33,taf. 3, fig. u. — MAAS, 1903, Scyphomedusen der Siboga Expcd., Monog. 1 1, p. 10, taf. 3, fign. 16-18. — Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at Harvard College, vol. 37, p. 30.

Bell globular, 15 to 17 mm. in diameter. 6 mainly solid, tapering tentacles, about as long as the bell-radius. 6 marginal sense-clubs, each with a terminal mass of concretionary crystals, arise from very shallow niches in bell-margin. There are 12 wide, shallow, slighty cleft marginal lappets. Ring-furrow on exumbrella not very deep. Central diskofexum- brella more than twice as wide as zone of pedalia. The 12 pedalia alternate with the lappets and are separated one from another by shallow furrows. Throat tube 4-sided, mouth cruci- form. There are 4 clusters of gastric filaments, each cluster consisting of about 20 filaments. The ring-sinus gives rise to 12 pouches in the radii of the tentacles and sense-organs and there is a marginal ring-canal as in A folia or Pertphylla. 4 interradial, sac-like, swollen gonads

arise from floor of subumbrella beyond the zone of the gastric filaments. Muscular system of subumbrella quite similar to that of Nattsithoe, but the ring-muscle is very poorly developed.

Stomach and gastric filaments brown, gonads yel- lowish-brown. Subumbrella muscles white, all other parts translucent.

VanhofFen describes a specimen from Dar es Salaam, east coast of Africa, and Maas describes another from the Malay Archipelago. Our description is derived mainly from that of Mass, his specimen being the more perfect. Vanhoffen's figure shows 6 gonads.

Atorella vanhoffeni Bigelow.

FIG. 362. — Atorelia subglobosa, after Maas in Siboga Expedition.

Atorella ranhofltni, BIGELOW, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 30, plates i, u, and n.

Bigelow had three specimens. In two of these the bell was 5 mm. high and 6 mm. wide, and one was 3 mm. high and 7 mm. in diameter. The ring furrow is a deep cleft. The entire exumbrella surface is besprinkled with wart-like, nema- tocyst-bearing prominences, thus being very different from the smooth surface of the bell of Atorella subglobosa. The 6 tentacles are each about as long as the bell-diameter. They taper outwardly but each terminates in a knob-like tip, instead ot having simple, pointed ends as in A. subglobosa. The 6 rhopalia closely resemble those of Atolla, but the exumbrella surface of its covering scale is covered with thickened ectoderm, not with a thin layer as in Atolla. There is a large lithocyst and ventral bulb, but no ocellus. There are 12 long, oval, marginal

FIG. 363. — Alorella vanhofleni, after H. B. Bigelow, in Mem. Mus. Comp. Zool. at Harvard College, 1909.

i ultONAT.E — AT()Hi:i.l.\. 569

lappets. The stomach is Hat and shallow and the 4 lips are short and thickened. The 4 intcrradial septal mules are narrow and the pcnadial ostia wide. 'I he gasmc cirri are arranged in 4 intenadial groups, each group arising trom a stout gelatinous stalk, and consist- ing of So to 100 filaments. The canal-system of the bell resembles that of Periphylla. The 4 penadial ostia of the central stomach lead into a wide ring-sinus, which gives rise on its outer side to 12 broad radial-canals in the radii of the tentacles and sense-organs. These radial- canals branch at their ends and unite to form a marginal festoon canal. I he ring-muscle of the subumbrella is very weak, but the subumbrella plates at the bases of the tentacles are \erv prominent.

There are 4 t;onads, each being a leaf-shaped hod\ folded so as to leave a deep groove along iis middle line on the inner surface, and this groo\e causes the gonad to appear as if double, although this is not truh the case tor each gonad is attached along a single line. The gonads are orange-\ ellou , all other parts colorless. This is a surface species. Bigelow records it from off the Pacific coast of Panama.

Order SEMAEOSTOME^E L. Agassiz, 1862.

Semaeostvmc.r, A'.A-M/, I-., iSh;, Conl. Nat. Hist. I'. S., \,,\. 4, pp. ij, i^.

Semoslamj-, HAM kit. iSSo, S\ t. .ler Me, Insert, p. 4'i<|.

Semttostomata, VAN tt. in- IN, iSSS. Jiibliothei :\ /.oologi, a. Heft. ',,pp.'>, 21; rood. Nordi chei Plankton, Nr. 1 1 , Acraspcda-, p. 45.

Semaeoslomj-, M\AX, !•) '• nd M'OIM hriiie .ler /o..l.. lid. i, p. 200; lyod, Fauna Arctica, Bd. 4, Lfg. 3, p. 504.

Diseomtdune (in part), HAtcKtt., 1880, S\^t. der Medusen, p. 450.

CHARACTERS OF THE SEMAEOSTOME^E.

Scyphomedusae without a coronal furrow anil without pedaha. With a simple, central mouth-opening, the 4 perradial angles of which are developed into large curtain-like or gelat- inous lips. With hollow tentacles and marginal rhopalia. The gonads are in sac-like folds ot the entodermal wall of the subumbrella. Without interradial septal nodes in the stomach.

The families of the Semaeostomeae are as follows:

(1) Pclagida- GE<;>:NBAI-R, 1856. The central stomach gives rise to completely separated, unbranched radiating pouches. No ling-canal. Tentailes .irise from the bell-margin between the clefts of the lappi-ts.

(2) Cy.ineid.e AcASIlZ, I... iS<i>. The central stomach gives rise to branched but completely separated radial-canals. No ririL^-canal. Tentacles arise from the floor of the subumbrella.

(3) Ulmarid.r HAM KM, 1880, sens ampl. The central stomach gives rise to simple or branched radial-canals which are put into connection one uirli .mother hy a marginal ring-canal.

A. Subfamily I'mbrosidii. The tentacles arise sine.lv from the clefts between the marginal lappets at the bell-

margin. Protrusive, sac-like gonads, without subgenital pits.

B. .Subfamilv Sthenonidii. The tentacles arise in linear clusters from the floor of the subumbrella.

<7. Subfamily Aun-lidii. The tentatle- anj lappets arise from the sides of the ciumbrella above the margin. Imayinated ^onajs with subgenital pits.

Family PELAGID^E Gegenbaur, 1856.

PtlagiJt, ilt'.i M!\I K, 1856, /fit. fiir wisM-n. /ool., H,l. S. pp. 210, 267. — AOASSIZ, L., 1861, Cont. Nat. Hist. U. S., vol. 4, pp 121, 163. — AGASSIZ, A., 1865, North AIIHT. Acal., p. 47. — HASCKKL, 1880, Syst. dcr Medusen, p. 499. — VON LKNDENFF.LD, 1884, Proc. Linnean Soc. Nn South Wales, vol. 9, p. 2(15. — CIAVS, iXSi,, Arbeit. /ool. Inst. I'niv. \\'cin., B.I. 7, p. no. — AI.ASM/ AM> .\Kvi.i:, iSijS, Bull. Mus. Comp. /ool. at Harvard Collcgf, vol. -,:. p. r. -1'iAr s, 1883, Organisation und Entwick. Medusen, p. 24. — VAMIOH-I-N, njofi, Nordisclics Plankton, Nr. n, p. 45.

1 AMU 1 CHARACTERS.

Scyphomedusae with 8 or 16 marginal sense-organs, 4 perradial and 4 interradial, and, when present, 8 adradial. 8 or more tentacles which arise singly from the clefts between the marginal lappets. 16 to 64 maiginal lappets. The mouth is simple and cruciform, and is situated at the extremity of an oesophagal tube, the 4 perradial corners of which are produced to form 4 long mouth-arms, the tree ed»es ot which are complexly crenulated. The simple, lenticular, central stomach gi\is rise to completely separated, radiating pouches the centrifugal ends of which give rise to simple, unbranched lappet-pouches. There is no ring-canal. The gonads occupy 4 interradial folds in the wall of the subumbrella. In some cases they project, but they are usually sunken, forming 4 pits in the floor of the subumbrella.

570 MEDUSAE OF THE WORLD.

The medusae of this family are readily distinguished from the Coronatae by the absence of a coronal furrow and by the remarkable development of the 4 perradial corners of the mouth, which extend outward as 4 long palps or mouth-arms, carrying the free edge of the lips along with them in double curtain-like fringes. Also the exumbrella of the Pelagidae is smooth and displays none of the complex sculpturing seen among the Coronatae; finally, the gastrovascular system of the medusae of the Pelagidae is simpler than in the Coronatae, for the central stomach is without interradial fusions of its upper and lower walls, and it con- sists merely in a wide, lenticular, central space which gives off completely separated, radiating pouches in the radii of the tentacles and sense-organs.

The Pelagidae are also closely related to the Cyaneidae. In the Cyaneidae, however, the tentacles arise from the floor of the subumbrella at some distance in from the bell-margin, whereas in the Pelagidae they arise from notches between the marginal lappets. Also the tentacles of the Cyaneidae are usually grouped in clusters, while in the Pelagidae they arise singly. A still further distinction lies in the fact that the radiating pouches of the stomach are simple in the Pelagidae, while in the Cyaneidae they give forth numerous blindly ending, non-anastomosing canals, which enter the marginal lappets.

Medusae of the genus Pelagia develop directly from the planula without going through a sessile scyphostoma stage. The planulae of Chysaora and Daetylometra, however, attach themselves and develop into Scyphostomae, which in the case of Chysaora is known to strobi- late and produce a number of ephyrae.

The Pelagidae are of world-wide distribution, but are most abundant in the tropical regions. Many of them congregate in great swarms in bays and estuaries, and none are known to live permanently at great depths.

The development of Pelagia has been studied by L. Agassiz (Cont. Nat. Hist. U. S.) and by A. O. Kowalevsky, 1874 (Memoirs of the Imperial Society of the Friends of Natural History, Anthropology and Ethnography of Moscow, vol. 10, p. 7, plate 3 [Russian text]). A synopsis of the genera of the Pelagidae follows:

Pelagia PERON AND LESUEUR, 1809. With 8 marginal sense-organs. 8 tentacles alternating with 8 marginal sense- organs, 1 6 marginal lappets.

Chr\saora PERON AND LESUEUR, 1809. With 8 marginal sense-organs. (3 X8) 24 tentacles, 3 between each successive pair of marginal sense-organs. 32 marginal lappets.

Dacl-ilomelra L. AGASSIZ, 1862. With 8 marginal sense-organs. (5X8) 40 tentacles, 5 between each successive pair of sense-organs. 48 marginal lappets.

Kuragea KISHINOUYE, 1902. (7X8) 56 tentacles, (8x8) 64 lappets.

Sanderia GOETTE, 1886. 16 marginal sense-organs, 16 tentacles, 32 cleft lappets. '

Genus PELAGIA Pe>on and Lesueur, 1809.

Pelagia, PERON ET LESUEUR, 1809, Ann. Mus. Hist. Nat. Paris, tome 14, p. 349. — ESCHSCHOLTZ, 1829, Syst. der Acalephen, p. 72. — AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 163. — HAECKEL, 1880, Syst. der Medusen, p. 504. — VAN- Hi'tviN, 1888. Bibliotheca Zoologica, Bd. I, Heft. 3, pp. 6, 21 ; 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, I'aldii'ia, Bd. 3, Lfg. I, p. 34; 1906, Nordisches Plankton, Nr. II, 14, 5. — MAAS, 1904, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 56; 1906, Revue Suisse de Zool., tome 14, p. 100: 1903, Scyphomedusen der Siboga Exped., Monog. 1 1, p. 29.

GENERIC CHARACTERS.

Pelagidae with 8 adradial tentacles, alternating with 8 rhopalia. With 16 marginal lappets. 16 radiating stomach-pouches in the rhopalar and tentacular radii, each of which ends in 2 side branches in the marginal lappets. No ring-canal.

The type species is Pelagia noctiluca of the Mediterranean, first described by Forskal, 1775, as Medusa noctiluca. At least 14 so-called "species" of Pelagia are known, I from the Mediterranean, I from the Mediterranean and Atlantic, 6 from the Atlantic, 5 from the Pacific, and I from the Indian Ocean. They are more abundant in warm or torrid regions, hut one species is found in Behring Sea and another near the Cape of Good Hope. All of the Atlantic species are closely related one to another, and future researches may demonstrate that they are only geographical races. In fact the distinctions between "species" have been largely determined upon preserved material, and some of them may be separated upon un- natural conditions of contraction due to the effects of preservation; thus Vanhoffen, 1888, distinguishes a number of "species" upon the folding and wrinkling observed in the exum- brella warts of preserved medusae. At present the "species" are in almost hopeless confusion, as will appear from the following table based largely upon Vanhoffen's work. Indeed it

PLATE 60.

Fig. I. Pclagta noctiluca, mature medusa, 1.25 times natural size. Naples Zoological Station, November 29, 1907.

Fig. 2. Pclagta noctiluca. Aboral view of a marginal sense-organ.

Fig. 3. Pelagia noctiluca. Side view of one of the nettlmg-warts near the mid-radius of the exumbrella.

Fig. 4. Nausit/ioe punctata. Oral view of mature female seven times the natural size. Tortugas, Florida, April 17, 1906.

Fig. 5. Nausithoe punctata. Side view of mature medusa showing sculptur- ing of exumbrella. Tortugas, Florida, June, 1906.

See page 553 for figures 4 and 5. Drawn from life, by the author.

MAYER

PLATE 60

--

•

•

sr.M MIMSTMMK.E — PELAUl \.

571

seems probable that the foldings observed by Vanhoffen in the nettle-warts are largely due to shrinkage in alcohol.

The medusae of Pelagia, being pelagic in all stages, are creatures of the high seas; and one would expect the species to be of world-wide distribution and at the same time to have developed many local varieties which are not very clearly differentiated from their parent stocks. I believe that all of the forms may be grouped into 4 cohorts as follows:

(1) P. nocliluca, ncglecta, and crassa, of the Mediterranean and Atlantic, with large, elongate nettle-warts over the

exumbrella.

(2) Allied to (i ) in the Pacifir. we tin I /'. favtola, Jenticulata, laliitiaaa, and fafillala with large oval, erect nettle-warts.

(3) P. cyanflla, ferla, diicoidea, phoipliora and minuta of the Atlantic with small, rounded nettle-warts.

(4) P. panopyra and placenta of the Pacific with small, flatly dome-like nettle-warts.

Cohorts (i) and (2] are closely related; and (5) and (4) form another group. As in Cyanea and AurAlia so in Pelagia we find that the Linnean system is inadequate to express the relationship of the numerous, closely related forms.

Synopsis of the Forms of Pelagia.

	P. noctiluca	P. cvandLi	P. panopyra	P. flavcola	P. discciidea	P. denticulata
	Peron et Lesueur.*	Peron et Lesueur/	Peron et Lesueur.	Eschscholtz =	Eschscholtz*.	Brandt. A
				P. tahitiana		variety of P.
				Agassiz and		flaveola(?)
				Mayer.
Width of disk in	60	5°	5°	1 6 to 30	70 to 80	60
mm.
Height of disk	32	40	30	8 to 15	15 to 20	5°
in mm.
Character of	Large, elongate,	Small, roundish,	Small, round,	Very large,	No warts. Ex-	Large, elon-
nettle-warts on	elliptical, with	thick-set. Fdiiriil	elliptical, with	thick-set, and	umbrella	gate over entire
exumbrella.	cross-foldings.	only in middle	longitudinal fur-	egg-shaped.	smooth ?	exumbrella.
		zone of disk.	row and cross-			Especially
			foldings.			thick at a'pex.
Shape of mar-	Square-cornered,	Twice as wide as	Quadratic.	Rounded, double,	Flat and cleft so	Quadratic.
ginal lappets.	quadratic.	high. Outer edge		twice as wide as	as to be double.
		convex.		long.
Length of	r or r —	r	2r	r	r_	0.5 r
mouth-tube in
terms of disk
radius.
Length of	2r4-	^r	V	r	y	V
mouth-arms in
terms of dis>k-
radius (r).
Where found.	Meiliterrancan.	Pernambuco,	Tropical Pacific.	Coast of Japan,	Cape of Good	Behring's Sea,
		coast of Brazil and		Paumotos	ll"l» , Africa.	Aleutian
		Florida to Cape		Islands, tropi-		Islands.
		Cod, in Gulf		cal Pacific.
		Stream.
Color.	Variable. Yellow-	Variable. Usually	Variable. Varying	Light-yclInwLsh.	Light-reddish.	Light violet-
	brown to reddish-	blue-viulrt to pah-	from light rose-red	Tentadr , * itron-	Palps rose-red.	red. Tentacles
	brown. Gonads	blue. NVuIr-warts	to violet-red.	yellow. Gonads	Tentacles pur-	red. Nettle-
	and tentacles us-	reddish-brown.	Mouth-arms more	brownish-yellow.	ple-red. Gonads	warts brown.
	ually dark-red.	Tentacles reddish-	violet. Gonads	N'ettle-warts	whitish.
	Mouth-arms yel-	purple.	more purple.	ti|>|«-d with
	lowish. Nettle-		NVttl.--warts	orange.
	warts reddixh-		violet.
	brown.

*Development without alternation of generations.

tDevelopment through a pelagic larva without alternation of generations.

JToo imperfectly known to be retained.

The remarkable development, which is direct, without a sessile larval stage, is described in detail under P. noctiluca anil /'. cyanella. The young medusa passes through a 4-tentacled stage, before acquiring its 8 adradial tentacles.

"Zonephyra corona" Agassiz and Mayer, 1902 (Mem. Museum Comp. Zool. at Harvard College, vol. 26, p. 157, pi. 4, figs. 19, 20), is probably a young Pelagia.

572

MEDUSAE OF THE WORLD.

Synopsis of the Forms of Pflagta — Continued.

	P.perla Haeckel. A variety of P. cyanella ( ?)	P. phosphora Haeckel.*	P. placenta Haeckel. A variety of P. panopyra.	P. neglecta VanhbfTen=a variety of P. noctiluca.	P. crassa Vanhbffen.	P. minuta Vanhoffen. = P. phos- phora (?)
Width of disk	50 to 60	40 to 50	40	53 to 6o	35	12 tO 25
in mm.
Height of disk	40 to 50	25 to 30	12	23 to 28	'3	3 to 6
in mm.
Character of nettle-warts on exumbrella.	Numerous, rounded, small, and flat.	Small, rounded, with longitudinal furrow and cross- foldings. None on upper third of exumbrella.	Numerous, thick- set but flat and small. Surface nodular.	Large, rounded to elliptical. Without longi- tudinal furrmv, but with cross- foldings.	Large, flat, ellip- tical with a longitudinal furrow and in- distinct cross- foldings. None at bell-margin.	Roumli'.l, small, thick- set, without longitudinal furrows, but with very thick cross-
						furrows.
Shape of mar- ginal lappets.	Quadratic, with concave outer edge.	Rounded, almost semicircular.	Twice as wide as high. Flatly rounded.	Quadratic.	Twice aswide as high.	Wider than high.
Length of mouth-tube in	o.33r	o.5r	o.5r	r~	o.5r	o.66r
terms of disk
radius.
Length of mouth-arms in	3r	IT	2r	2.5r	2r	2r
terms of disk-
radius (r).
Where found.	Atlantic coast of Europe.	Tropical parts of the Atlantic. West coast of Africa.	Tropical Pacific, South America, Philippines.	Mediterranean and coast of Africa.	In middle of tropical Atlan- tic.	Coast of Brazil, Per- nambuco.
Color.	Variable. Orange to rose-red or	Variable. Rose- red to violet-red	?	?	?	?
	flesh-colored, or with rusty-yel- low flecks. Nettle-warts orange. Tenta-	or purple. Arms, ribs, tentacles, and gonads usually darker red than the bell.
	cles and gonads red.

*Development through a pelagic larva without strobilization or alternation of generation, Haeckel, 1867.

Griffiths and Platt, 1895 (Nature, vol. 52, p. 564), find that the violet pigment of Pelagia has the composition C20 HI7 NO7. It is soluble in alcohol, ether, and acetic acid, and especially soluble in CS2. Insoluble in water. It gives no characteristic absorption bands. It is thus quite distinct from the blue coloring matter of Hydromedusae as determined by Colasanti, 1888 (Centralblatt fur Physiol., Bd. 2, p. 10).

Pelagia noctiluca Pgron and Lesueur.

Plate 60, figs, i to 3.

Medusa noctiluca, FORSKAL, 1775, Descript anim. itin. orient., p. 109.

Pelagia noctiluca, PERON ET LESUEUR, 1809, Annal. du Mus. Hist. Nat., tome 14, p. 350; P. pur/tura, Aurrllia plio.<[>horica, loc.cit., pp. 350, 358. — KROHN, 1855, Miiller's Archiv. Anat. Physiol., p. 491, taf. 20 (development). — HAFCKF.L, 1880, Syst. der Medusen. p. 505 (list of authors and names). — KOWAI-EVSKY, 1873, Mem. Imp. Sue. Lovers of Nat. Hist.. Moscow, vol. 10, part. 2, p. 7, plate 3 (development). — HAMANN, 1883, Zeit. fur wissen.Zool., Bd. 38, p. 422, taf. 32 (develop- ment and structure of gonads). — METSCHNIKOFF, 1886, Embryol. Studien an Medusen, Wien., p. 24 (egg); 67 (segmenta- tion); loo (larva); taf. 10, fign. 23-28. — MONACO, Prince of, 1887, Comp. Rend. Paris, tome 104, p. 452 (swarming habits of the medusa). — VANHOFFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 8, taf. I, fign. 5, 6; taf. 6, fign. 1-5; 1908, Deutsch. Siidpolar Expedition, 1901-1903, Bd. 10, Zool. 2, p. 38. — GOFTTE, 1893, ^eir- rur wissen. Zool., Bd. 55, p. 659, 1 1 fign., taf. 30-31; 1893, Sitzungsber. Akad. Wissen. Berlin, p. 853 (development). — SCHAXEL, 1910, Zool. Anzeiger, Bd. 35, p. 407 (histology of obgenesis).

The following is a description of a typical, adult specimen from the Bay of Naples: Disk somewhat higher than a hemisphere when contracted, but flatter than a hemisphere

SKMAF.OSTOME.E — PKLAG1A. 573

when expanded. In ordinary contraction if is about 49 to 55 mm. in diameter and 31 mm. high. Sides of bell relatively straight and sloping, the apex flat. Numerous nettle-warts over the cxumhrclla, arranged in more or less irregular lines radiating from aboral apex of exumbrella. These watts are rich orange-red in color and are elongate and linear, some- times with, bur more often without, cross-foldings. Near the bell-margin, however, they lose their linear shape and become small, simple, and more or less oval.

The 8 marginal sense-organs are set in deep niches in the perradii and interradii. The sense-club has no ocellus, but contains only a terminal mass of deeply pigmented orange-colored ci \siallinc concretions of entodermal origin. There is no sensory pit in the exumbrella above the sense-club. The 8 hollow, tapering tentacles are each about twice '115 mm.) as long as the bell-diameter.

There are 16 subrectangular marginal lappets, with shallow median notches and rounded angles. The septum between the ultimate branches of the radiating stomach-pouches in the marginal lappets is twice as wide as the ultimate pouches themselves. The 4-sided throat- tube is as long as the bell-radius. The 4 lanceolate lips or palps, with their complexly folded margins are each about 1.33 as long as the bell-diameter. Thus in an adult medusa with a disk 49 mm. wide the palps were 68 mm. long.

The bell has a rich rose-purple tinge; the gonads, the entodermal cores and the ten- tacles being especially deep in this color. The warts upon the exumbrella and along the outer edt;es ot the palps are orange-brownish red.

This medusa is abundant at times in the Mediterranean especially in summer, although laiiM- specimens aie lately seen in winter. It may be locally abundant during several suc- cessive seasons and then vanish for years. For manv years it was all but unknown in the l!a\ nl Naples bur since 1900 it has been one of the commonest Scyphomedusze in this region. It ranges widely over the warm regions of the Atlantic.

The development has been studied by Krohn, Kowalevsky, Hamann, Goette, Hyde, and Metschnikoff. Hamann, 1883, has made a detailed study of the development of the gonads, and their structure has been described by the brothers Hertwig, 1878. They appear as 4 inrei radial, elongate ridges in the entoderm of the subumbrella. The entoderm forms a series ot follicles in which the sex-cells develop and then migrate into a gelatinous lamella between the layers of entoderm.

According to Metschnikorr", the egg is violet-brown and is laid between 12 and 2 in the afternoon, in December, in the Mediterranean. Segmentation is total and nearly equal, and a \ ery large central segmentation-cavity is formed. The gastrula results from invagination at the hinder end of the body. The blastopore does not close, but forms the mouth of the larva. Thus, according to Goette, 1893, the mouth is ectodermal and forms by invagination at the hinder end of the larva, but the invaginated sac by no means fills the segmentation cauiy. The first pair of stomach-pouches arise from the entoderm and are 180° apart, then follows an ectodermal pair 90° away from the first. The latter then deselop 2 lateral pouches each, and at a later period the entodermal pair each gives rise to 2 lateral pouches, thus giving a larva with 6 ectodermal and 6 entodermal stomach-pouches; finally the ectodermal pouches give rise to 4 new adradial pouches and the larva has 16 stomach-pouches — 10 ectodermal and f> entodermal. I here is thus a striking analogy between its development and that of the scyphostoma nt .///;,///.;, acconlin<; to Goette.

The external features of the transformation of the free-swimming larva into the medusa have been studied by Krohn (1855), Kowalevsky (1873), etc. The mouth-end of the larva becomes expanded and crater-like, with the mouth at summit of central cone of crater. The dcpnsscd region around the cone becomes the subumbrella. The lappets, into which the gastrovascular ca\itv is continued, grow out at intervals around the margin. The covering of cilia is lost from the body of the larva and it begins to swim by means of rhythmical con- i racoons ot its oral disk. Thus the free-swimming scyphostoma is converted into a medusa without strobilization (see Goette, 1893.)

Reasoning by analogy from the excellent work of Hyde, 1894 (Zeit. fur wissen. Zool., Hd. SS. p. SS1 li upon •Inrcllid, it is probable that only the subumbrella floor of the second pair of evaginatrd gastric pouches is formed from ectoderm, their exumbrella sides being of entoderm. iSee also Had/i's work upon Chrysaora.}

574 MEDUS.E OF THE WORLD.

Pelagia noctiluca var. "neglecta." Pelagia neglecta, VANHOFFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 9, taf. 6, fign. 6-12.

This variety is distinguished by the large, elliptical nematocyst-warts upon its exumbrella. These warts are usually about twice as long as they are wide and display cross-furrows. Speci- mens in which the bell is 53 to 60 mm. wide have a bell-height of 23 to 28 mm. Mouth-tube 15 to 25 mm. long and mouth-arms 68 to 85 mm. Color (?) This species is found at Naples and at the Canary Islands. Were it not for the very large, elliptical nettle-warts of the exum- brella, it would be identical with the typical Pelagia noctiluca Peron and Lesueur. It is so closely related to P. noctiluca that I believe in view of the ordinary variability of individuals of the same species in Scyphomedusae, it had best be omitted from further consideration and merged with P. noctiluca.

Pelagia cyanella Pe'ron and Lesueur.

Plate 61, fig. I.

Medusa pelagica, LINNE, 1758, Systema Naturae, Ed. 10, p. 660.

Medusa pelagica, LINNE, 1766, Systema Nature, Ed. 12, p. 1098. — 1788 (Gmelin), tomus I, pars 6, p. 3154.

Pelagia cyanella, PERON ET LESUEUR, 1809, Ann. Mus. Hist. Nat. Paris, torn. 14, p. 349, No. 66.

Dianaea cyanella, LAMARCK, 1816, Hist. Anim. sans vert., tome 2, p. 507.

Pelagia cyanella, ESCHSCHOLTZ, 1829, Syst. der Acalephen, p. 75, taf. 6, fig. I. — Bosc, 1830, Hist. Nat. des Vers., Ed. 2, tome 2, p. 140, plate 17, fig. 3. — AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 128, 164; Ibid., 1860, vol. 3, plate 12, figs. 1-16. — AGASSIZ, A., 1865, North Amer. Acal., p. 47, fig. 68. — HAF.CKEL, 1880, Syst. der Medusen, p. 507. — VAN- HOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 22. — BIGELOW, 1890, Johns Hopkins Univ. Circ., vol. 9, No. 80, p. 66. — HARGITT, 1904, Bull. U. S. Bureau of Fisheries, vol. 24, p. 70, plate 7, fig. I.

This American medusa is very closely related to the European P. noctiluca, of which it is apparently only a local variety.

Bell about 40 mm. high and 50 mm. broad; somewhat fuller than a hemisphere, being a little less broad at margin than a short distance above. Numerous small wart-like nemato-

o

cyst capsules are sprinkled thickly over the exumbrella and are especially thick in a zone at about mid-height of bell; these protuberances are reddish in color and tend to be arranged in radiating lines. 8 very long, highly contractile, hollow tentacles alternate with 8 marginal sense-organs. Each sense-club is set within a niche between two adjacent lappets and is protected on the outer side by a partial web between the lappets. The club is hollow and has no ocellus, but contains a terminal, entodermal mass of crystalline concretions which are deeply pigmented. 1 6 marginal lappets, hemispherical in shape. There is a long, narrow, 4-sided proboscis, the radial corners of which extend downward as 4 long, flexible mouth-arms, the free edges of which are complexly crenulated. The proboscis, together with the mouth-arms, or palps, is about 3 times as long as bell-height. There are 4 complexly folded horse-shoe- shaped gonads in mterradial positions upon the floor of the subuihbrella, and immediately centripetal to them are 4 subgemtal pits or cavities extending inward from the outer surface of the subumbrella. The quadrangular oesophagus leads into a circular, disk-shaped, central stomach which gives rise to 16 radial pouches extending outward in the radii of the sense- organs and tentacles. Each of these pouches gives off a pair of unbranched, curved canals which enter the lappets, but do not form a ring-sinus. There are 1 6 well-developed strands of radiating muscle fibers in the wall of the exumbrella adjacent to the gastrovascular cavity. These extend outward in the radii of the tentacles and sense-organs, and fork as they approach the bell-margin.

The color is quite variable, sometimes bluish, sometimes slightly yellowish. Exumbrella and mouth-arms sprinkled over with brownish-red nettling-warts, tentacles reddish-purple.

This species is found among the West Indies and Florida Reefs, and in summer it may drift northward in the Gulf Stream so as to appear off the southern coast of New England from July to September.

L. Agassiz, 1860 and 1862, found that the planulae of this species, as in P. noctiluca, develop directly into medusae without going through a sessile scyphostoma stage and without alternations of generations. The planulae are set free into the water where each develops into a single medusa. The minute details of the development have been worked out upon Pelagia noctiluca by Metschnikoff, 1886 (Emb. Stud, an Medusen, Wien.), and by Goette, 1893 (Zeit. fur wissen. Zool., Bd. 55, pp. 659-692). The gastrula is formed by invagination. The first pair of radial stomach-pouches appear, according to Goette, as outpocketings from the

PLATE 61.

Pclngia fytinflla, from the borders of the Gulf Stream off Woods Hole, Massachusetts.

Drawn from life, by the late Prof. William K. Brooks and kindly pre- sented for publication in this work.

BROOKS

M

SKM.U:C>STH\I I .1: PELAQ] \.

entoderm and these are quickly followed by another pair from the ectoderm of the throat- tube, tlu- t\\n latter being <>o away t'rom the former. Tin- ectodermal pouches then give rise each to two side branches and sunn thereafter the entodermal do the same. Thus the cen- tral stomach comes to base 12 radial pouches. 4 more radial pouches are soon formed from the ectodermal pouches, so that the voun«; medusa finally possesses 16 radial pouches. It follows ill adult medusa that the center of I he ex umbrella side of the central stomach is derived from entoderm. 2 diametrically opposed, perradml pouches are ectodermal in origin and the othei Z an i-ntodermal. The 4 imerradial pom IKS are ectodermal, and of the 8 adradial pouches, 4 ;irc ectodermal and 4 entodermal. The wall of the cjesophagus is of ectodermal "iMj.m. I he \oting medusa soon develops S lobes which bifurcate. omng 16 marginal lap- pets. The 8 marginal sensc-oigans develop before the tentacles. The mouth is at first a sim- ple, round opening ar the center of the crater-like ectodermal depression. It soon acquires 4 lips, but the mouth-arms do not develop until a later stage. It is probable that the ecto- derm dms not take so large a share in the formation of the Stomach-pouches as Goette sup- poses (see Chrysaora and Aurellia).

Pelagia panopyra P£ron and Lesueur.

MfJma f>anop\ra, PERON- >T L>si M R, 1807, Voyage aux Torres Australia, planche 31, fig. 2.

HI panof>\ra, PERON F.T 1 . ! i i , i ^09, Annal. du Mu^. Hist. N.U., tome 14. p. 349. — ESCHSCHOLTZ, 1892, Syst. der Acal., ,, I. if. 6, tii'. 2. -BnAM>r, lS',S, Mi'-in. AcaJ. St. Petersbmirg, tume 4, srr. 6, Sci. Nat., p. 382, taf. 14, fig. I; taf. 14 A. fii^n. 1-5.- -HAH k'KL, iSSo, Syst. tier Medusi-n, p. 509 (literature). — VAKHOPFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 14. — Ff.WKrs, [SS«j, American Naturalist, vol. 23, p. 592, fig. i; 1889, Bull. Essex Inst. Salem, vol. II, No. 7, p. 122, plate <;, fig. i . — MAAS, 1903, Scyphomeilusen iler Siboga ExpeJ., Monog. 1 1, p. 29. — MAYKR, 1906, Bull. V. S. Fish Com- mis-icm, \M!. ;;. |-.nt ;. p. 1 1 ;.). pl.itc- i, fig:.. ;, 4. BI..I i nw, II. K., i')O'), Mem. Museum Comp.Zool. at Hairard College, \« >!. ". p. 4 ; .- \i \ \ , M/ -i. \M':, i n.ll. AL.t.L U'lvscn. Munclu-n, Suppl. BJ., i Abhandl. 8, p. 43. — KISHINOUYE, 1910, fnnriial Collrgr Sri. Tokvn, vol. zy. an. <j. p. ').

The characters of this widely distributed Pacific form are described in the table under the genus Pel<i«in. It is distinguished from the closely allied P. flaveola by its pink colora- tion, whereas P. fl<n-?olti is yellowish. Moreover the nettle-warts of P. panopyra are low and domelike, while in P. flaveola they are erect and bluntly pointed.

Fir,. ;f>4- -Pelagia favtola, from T.iMii. .ifrrr Agassiz and Mayer, in Mrm. •I ' 'up. Zool. at Harvard College.

P. f>annf>\ra is common off the coast of California and extends across the Pacific to the Malay Archipelago, and northward to Japan.

Vanhoffen »i\es the dimensions of a specimen as follows: Bel! 27 mm. wide, 6 mm. high; month-tube 15 mm. long; lips i~ mm. long.

\\ hen vouno the medusa has only 4 tentacles. When the bell is 15 mm. wide the gonads

begin to develop.

Pelagia panopyra var. placenta.

Petunia placenta, HAVCKFI., iSSi . Mcdusen, p. 510.— VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. n,

laf. 6, fig. 20.

This appears to be a very close variety of /'. p,iiir>f>\rn. Both medusa? are widely dis- tributed over the tropical Pacific. See synoptic table of forms of Pi-la gi<i. I believe that this

576 MEDUS/E OF THE WORLD.

form can not be distinguished from P. placenta for I have found specimens which intergrade in one character or another. Many specimens of this medusa were found by the Albatross in the Philippine Islands in March and April, 1908. The dimensions in mm. of a mature speci- men are as follows: Diameter of bell, 35; height of bell, 15; length of oesophagus, 14; length ot lips, 30; length of tentacles, 50.

The largest exumbrella warts are near the center of the bell and they decrease in size toward the margin, where they are very small. The surface of these warts is nodular and lacks the cross-foldings seen in the typical P. panopyra, but this character mtergrades.

Pelagia flaveola Eschscholtz.

Pelagia faveola, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 76, taf. 6, fig. 3. — GOETTE, 1886, Sitzungsber. Akad. Wissen. Berlin,

Jahrg. 1886, p. 883.

( ?) Pelagia denticulata, BRANDT, J. F., 1838, Mem. Acad. Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 383, taf. 14, fig. 2. Pelagia tahitiana, AGASSIZ, A., AND MAYER, 1901, Mem. Museum Comp. Zool. at Harvard College, vol. 26, p. 158, plate 8, figs.

.34.35- Pelagia papillata, HAECKEL, 1880, loc.cii., p. 509.

For description see synoptic table of forms of Pelagia, and figure 364. This form is distinguished by its yellow color and long, pointed nettle-warts which cluster thickly at the aboral apex of the bell. Tropical Pacific from South America to East Africa.

Pelagia perla Haeckel.

Medusa perla, SLABBER, 1781, Physikal. Belust., p. 58, taf. 13, fign. i, 2.

Pelagia cyanella, FORBES, 1847, Annals and Mag. Nat. Hist., vol. 19, p. 390, plate 9, fig. 5.

Pelagia perla, HAECKEL, 1880, Syst. der Medusen, p. 506. — MAAS, 1904, Result Camp. Sci. Prince de Monaco, fasc. 28, p. 57. —

DF.LAP, M.S., 1906, Fisheries of Ireland, Sci. Invert., 1 905, No. 7, p. 22, I plate. — VANHOFFF.N, 1906, Nordisches Plankton,

Nr. 11, p. 45, fign. 6, 7. — BROWNE, 1908, Trans. Royal Soc. Edinburgh, vol. 46, p. 242. Pelagia discoidea, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 76, taf. 7, fig. i.

This appears to be a North Atlantic variety of P. cyanflla. The nettle-warts of the exumbrella are more numerous and the outer margin of the lappets are concave instead of convex as in P. cvanella. For description see the synoptic table of the forms of Pelagia.

P. discoidea from the Cape of Good Hope is probably identical with /•*. perln.

Pelagia phosphora Haeckel.

Pelagia phosphora, HAECKEL, 1880, Syst. der Medusen, p. 506. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, pp. 1 1, 22, taf. 6, fign. 18, 19; 1892, Ergeb. der Plankton Expedition, Bd. 2, K. d., p. 19; 1902, Wissen. Ergeb. deutsch.Tiefsee Expedition, Valdivia, Bd. 3, Lfg. I, p. 36.

This form is closely related to P. cyanella, but may possibly be distinguished from it by the larger nettling-warts upon the exumbrella, which are round and 0.5 to I mm. in diame- ter and each gives rise to a longitudinal comb-like crest. Marginal lappets wider than long. (Esophagus about one-fouith as long as bell-diameter, mouth-arms about equal to bell-diam- eter in length. Bell hemispherical, 40 to 50 mm. in diameter. Color quite variable, either purple, violet, or reddish; gonads, tentacles, and median ribs ot the mouth-arms of darker color than other parts of the animal.

Found in the eastern Atlantic from 58° N. to 42° S. lat.; also in the Indian Ocean, being especially abundant in the tropics.

Vanhoffen, 1902, gives the following dimensions for this species: Diameter of bell, 76 mm.; height of bell, 25 mm.; tentacles, 76 mm. long; nettling-warts on exumbrella, 2.5 mm. high.

Pelagia "miniita" Vanhoffen, 1888 (Bibliotheca Zoologica", Heft. 3, p. 12, taf. 6, fign. 16, 17), is a variety of, or possibly the young of, P. phosphora. The nettling-warts on the exumbrella, in specimens preserved in alcohol, are elongate with numerous transverse furrows (due to contraction ?). No mature specimens were described by Vanhoffen. Found at Pernambuco, Brazil, early in July.

Pelagia crassa Vanhoffen.

Pelagia crassa, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, pp. 10, 22, taf. I, fign. I, 2; taf. 6, fign. 13, 14. Pelagia crassa var. sublaevis, Ibid., p. II, taf. 6, fig. 15.

This appears to be a small variety of P. noctiluca.

Bell about 13 mm. high and about 35 mm. in diameter. Gelatinous substance of exum- brella thicker than in any other Pelagia. Marginal lappets about twice as wide as long.

SEMAEOSTOME.E — PELAGIA, CHRYSAORA. 577

(Esophagus shorter than in P. cyanella, only about one-quarter as long as bell-diameter. Mouth-arms also much shorter, only about as long as bell-diameter. Nettling-warts upon exumbrella larger and differently arranged than in either P. cyanella or P. phosp/iora; they are concentrated near apex of bell and not found near margin, elliptical in shape, sometimes quite flat, or with a well-developed longitudinal comb-like ridge crossed by corrugations. The largest warts are found at the apex of the exumbrella and they become smaller toward the periphery. In the variety subhrvis the bell is arched and more hemispherical than in P. crassa. The gelatinous substance is thicker and the nettling-warts are larger and flatter than in P. crassa. These forms are found in the middle of the tropical Atlantic between Africa and South America.

Genus CHRYSAORA PSron and Lesueur, 1809.

Chrysaora, P£RON ET LESUF.UR, 1809, Ann. Mus. Hist.

. _Q Un....n'r 1 0 1 tt Vf.l.v* Ar-l.t .I..C £<-i Qh

C/;r,

The type species is C. meJiterranca Peron and Lesueur, of the Mediterranean.

GENERIC CHARACTERS.

Pelagidae with 8 marginal sense-organs, 24 tentacles (3 in each octant), and with 32 marginal lappets.

The medusae of Dactylometra pass through a "Chrysaora stage" in their development, and there can be but little doubt that some of the so-called Chrvsnorn medusae are only im- mature Dactylometra. The difficulty in distinguishing Chrysaora is still further complicated by the very variable, individual coloration of these medusae, and by the fact that some species of Dactylometra, such as D. quinquecirrha itself, become sexually mature in the Chrysaora stage when living in brackish water. The Chrysaora and Dactylometra medusae are widely distributed over the tropical and temperate seas and there are many local races. I believe that future study will reduce the species to two or three, with numerous local varieties, as in Pclavia or Cyanea.

C/u-ysuoni hysoscella of the Mediterranean and Atlantic, and C. mclanaster and C. lichola of the North Pacific appear to be distinct species, while the other so-called species may be varieties of the three above named or merely immature specimens of Dactylometra. C. helvola and C. melanaster finally develop small, lateral lappets upon the sides of their 16 ocular lappets and thus approach the Dactylometra condition in having 48 marginal lappets. The tentacles, however, remain 24 (3 in each octant) as in Chrysaora. L. Agassiz proposes the generic name Melanaster for Pelagidae with 48 lappets and 24 tentacles, but as this appears to be but a transient stage in the process of growth of Dactylometra, or a late stage in the devel- opment of Chrysaora, we prefer not to adopt it.

Chrysaora hysoscella, which is probably identical with C. mediterranea, is often hermaph- roditic; young individuals being male, middle-aged ones hermaphroditic, and old ones female. In other cases, however, the medusae are throughout life of one sex; while in others male saccules develop among the old female gonads, and in other parts of the entodermal layer of the subumbrella.

The development of Chrysaora is through a sessile scyphostoma-stage, and the ephyra is produced by polydiscus strobilization. The ephyra passes through an 8-tentacled stage in which it recalls the condition seen in the adult of Pelagia.

The mode of origin of the 4 primary stomach-pouches of the scyphostoma, and their derivatives, has been the subject of a prolonged discussion between Claus and Goette, and others. The view of Goette that the etsophagus of the scyphostoma is derived from invaginated ectoderm received support from Hyde, and was generally accepted until 1907 when Hadzi and also Heric (Arbeit. Zool. Inst. Wien, Bd. 17, Heft, i) made further studies of the development of Chrysaora. It should also be remembered that R. P. Bigelow, 1900, in his study of the development of Cassia/yea is in accord with the views which were later put forth by Had/.i.

578

MEDUS.E OF THE WORLD.

Hadzi finds that some of the free-swimming planulae of Chrysaora are 4 or 5 times as large as others. They swim with the broad end forward and soon settle upon nlva, etc., attaching by means of their forward ends. The entoderm, which was previously a solid mass, then hollows out and the larva becomes two-layered, and the uppermost (the former posterior) end becomes the widest. The mouth then breaks through, the oral pole flattens laterally, and 4 tentacles develop, 2 in the short and 2 at the ends of the long diameter. The stomach-pouches do not begin to form until after the mouth and 4 tentacles have developed.

The view of Claus has received strong support from Hadzi who casts serious doubt upon Geotte's interpretation that the oesophagus of the scyphostoma is always composed of invag- inated ectoderm.

Hadzi, whose research upon Chrysaora appears to have been carefully studied, finds that the oesophagus of the scyphostoma is entodermal and that the mouth breaks through from the inside, the entoderm thus taking the active share in its formation, and no invagination of ecto- derm occurring. Indeed Hadzi finds that the cells lining the throat of the scyphostoma resem- ble ectodermal cells in having nematocyst capsules and glands, but they are nevertheless solely of entodermal origin. From this it follows that the 4 primary stomach-pouches are also ento- dermal, not 2 ectodermal and 2 entodermal as claimed by Goette. Hadzi finds also that the 4 intertentacular taeniolae are formed from 4 simple, longitudinal infoldings of the entoderm of the stomach wall, the ectoderm taking no part in their formation. The primary stomach- pouches are thus the passive result of the infoldings which form the taeniolae, not of an active outgrowth of pouches as Goette believes.

Hadzi's view appears to be the more reasonable, for if Goette were correct one half of the gonads would be ectodermal and one half entodermal, whereas according to Hadzi they are all entodermal; moreover, according to Goette, the mouth of the first ephyra set tree in strobili- zation has its oesophagus lined with ectoderm, while those ephyrae which follow it have their throats lined with entoderm, an anomalous condition. According to Hadzi and Heric, how- ever, all of the ephyrae have their throats lined with entoderm.

Heric finds in the stabilization of the scyphostoma of Chrysaora that with the exception of the terminal ephyra all of the mouth-tubes of the chain of ephyrae are formed from the connecting tube which joins all of the ephyrae together. The external wall of this connecting tube is ectodermal and its inner wall entodermal. 4 perradial clefts develop in the side wall of each tube near the upper end where it joins with the exumbrella of the overlying ephyra. The lower edges of these clefts grow out- ward and form the 4 lips of the ephyra, while the 4 connections are interradial and are in the radii of the taemolae which consti- tute their inner sides.

The 4 subgemtal cavities of the ephyra are new formations and not derived from the 4 funnel-cavities of the scyphostoma. The 4 interradial septa of the stomach-cavity of the ephyra are, however, derived from the taemolae of the scyphostoma. These soon disappear, and the central stomach of the medusa is a simple lenticular space.

The forms of Chrysaora are so imperfectly separated one from another that were it not for the fact that many minute distinc- tions have been pointed out between them, I would greatly prefer to consider them all to be one variable species, C. h ysoscella. However, we may possibly distinguish more or less vaguely:

FIG. 365. — Diagrammatic section of a strobilla of Chrvsaora after Heric, in Arbeit. Zool. Inst. Wien.

ah, perradial cleft, am, beginning of the lip. />, /, /, stages in the growth of the throat-tube. s m, septal muscle. Ectoderm cross-hatched, entoderm plain, intermediate lamella dotted.

C. hysoscelIa=C mediterranea with its varieties biossevillei and plocamia (?)

of the Atlantic, Mediterranean, and South Pacific. C. heh'ola, with its varieties calliparea, and cliinensis of the Pacific and

Indian Oceans. C. melanaster with its variety gilberti of the North Pacific.

I believe that a study of the following synoptic table will convince one that we have here only one species, the varieties of which defy classification in terms of the Linnean system.

SKM A KOSTOM K.K — CHH YS A < »K A .

579

Synopsis of the "Species" of Chrysaora.

	C. mediterranea Peron et Lcsueur=C. hyso- scella.*	C. hysoscella Esch- scholtz.j* Identical with C. mediterranea.	C. blossevillei Lesson, a variety of C. hyso- Bcelia.J	C. fulgida"Hacckel = Rhi/ostmna fulgidum Revn.m.l; a variety of 1 il cell a.
Shape of disk.	Flatly rounded.	Flatly rounded.	Nearly hemispherical.	i I a-rical.
Width of disk in mm.	100 to 300	100 to 200	100	300 to 400
Height of disk in mm.	40 to 80	40 to 60	40	100 to 200
Shape of marginal lap-	Flatly rounded. The	All semicircular and of	All half-egg-shaped	Alt .tlil.e. Smiicircular.
pets.	16 ocular lappets only	(•(jii.il \viilth. The i <•	(oval). Ocular and
	half as wide as the 16	ocular lappets project	interoeular cleft
,	tentacular lappets.	more than the 16 ten-	twice as deep as clefts
		tacular lappets.	which alternate with
			them.
Shape of the 8 ocular	At periphery of central	In middle, the 8 ocular	In middle, ocular	p
stomach-pouches.	stomach as wide, in the	pouches are same	pouches are equal to
	middle three-fourths, at	width as 8 interocular.	tentacular pouches in
	margin half as wide as	At bell-margin, ocular	\\i 1th. At margin,
	tentacular pouches.	pouches are only one-	ocular pouches an: onlv
		third as wide as ten-	half as wide as the ten-
		tacular pouches.	tacular.
Shape of curtain-like lips	Tapering from base to pointed ends. Edges	Tapering from base to pointed ends. Edges	Lancet-shaped. Taper- ing with folded margins	I. ,uu rl-^liajn1,!, widest in middle where they
	arc curtain-like and	very much folded.		are as wide as o.$r.
	very complexly folded.
Length of mouth cur-	3 lo 4r	2r	zr	4 lo 6r
tains (lips) in terms of
disk-radius r.
Length of longest ten-	zr	2r	r	r. Rcvnaud figures only
tacles in terms of disk-				1 6 tentacles.
radius r.
Color.	Variable. Disk is	Variable, and similar	Bell amber to rusty in	Bell vclli >\\ ish-hro\vn.
	whitish to yellow. Us-	toC. mediterranea, but	color. M'Hiih-.irins	Radial streaks and
	ually there is a reddish	usually more intense.	rusty-yelluw.	marginal lappets red-
	ring around apex, ani:			dish-brown. Mouth-
	radiating from this are			arms reddish; gonads
	16 radial streaks.			carmine.
Where found.	Mediterranean.	Atlantic coasts of	Coast of Brazil, Island	Cape of Good Hope,
		Europe.	of Santa Catharina to	False B.iv, Algoa Bay,
			Pernambuco.	Africa .

*Development through alternation of generations with stabilization (Claus).

•(•Development as in C. medilerrartea. Haeckel found a specimen 160 mm. wide, with 40 tentacles, and 48 marginal lappets as in Dactylometra.

JOne of Vanhbffcn's specimens had 4 tentacles in one octant. See also L. Agassiz, 1862, Cont. Mat. Hist. U. S., vol. 4, pp. 127, 166.

Chrysaora hysoscella Eschscholtz.

I'nira miiiina, etc., BORI.ASF., 1758, Nat. Hist. Cornwall, p. 256, plate 25, figs, vn and vui.

MrJusa h\soicrlla, I..INNK, 1766, Systema Nature, Ed. 12, p. 1097.

Chrysaora cyclonata, aspilonota, spilo^ona, spilhrmigona, pleurophora, lesueurii, macrogona, htplanerna, medlterraneatrt^ott F.T LESL'EUR, 1809, Annal. du Mus. Hist. Nat., tome 14, pp. 365, 366.

Chrysaora hysoscella, Esc HSCHOLTZ, 1829, Syst. der Acal., p. 79, taf. 7, fig. 2.— CLAUS, 1877, Dcnksch. Wicn. Acad., p. 33, taf. 6, 7. — KRUKENRtRn, 1 880, Zool. Anzriger, Jahrg-3, p.3o6.(the medusa contains oq.?:; t.icjd.', percent of water).— GRAEFKE, 1884, Arbeit. Zool. Inst. \Vu-n., Bd. ;, p. 342.— VANHiirrtN, 1908, Dcut-.. h, Sudpolar i:\pr, hti,.,,, 1(,|. ,o. /."..!. :. p. 39.

Chr-isaora mtaittrran,,i+ C. i,osfelrs, HAICEIL, l88o, Syst. d.-r Mcdusen, pp. 511, 513, taf. 31, fign. 1-3 (list of literature).

Clir \saora mejiterranra, VANHUKFIN, lSS8, Bibliothcca Zoologica, Bd. i, Heft 3, p. 14.

C.lirwaorti livsoscrlla=C. mniiurranea, VANHOFFF.N, 1906, NorJischrs Plankton, STr. n, p. 47, lign. 9-10 a, b.

Chr \saora isoscrlfs, DFI.AP, M. J., 1901, Irish Naturalist, vol. 10, p. 27 (rearing the larva in an aquarium).

For a synopsis of" the characters of C. hysoscella, see table of characters of Cliry.«ir>r,i.

There appear to be no definite distinctions between C.liryfii'irn "mediterranea" of the Mediterranean and C. hysoscella of the Atlantic coasts of France, England, Germany, and Holland, and in the entrance to the Baltic Sea. It is probable that the Chrysaora of the Chesapeake Bay, in America, is identical with that of Europe, but I believe the Chesapeake medusa to be only a brackish-water variety of Dactylometra quinquecirrha, which becomes mature in the 24 tentacle stage. Judging from Haeckel's figures the Mediterranean medusa is more highly colored than that of the northern shores of Europe. In the Chesapeake the

580

MEDUSA OF THE WORLD.

Synopsis of the "Species" of Chrysaora — Continued.

	C. plocamia Haeckel, a variety of C. blossevillei.	C. helvola Brandt.	C. calliparea Haeckel, a variety of C. helvola.	C. chinensis Van- hoffen, a variety of C. helvola.	C. melanaster.* See C. gilberti Kishinouye.
Shape of disk.	Hemispherical.	Hemispherical, or	Flatly rounded to	Flatly rounded to	Hemispherical or
		flatter. Exum-	hemispherical.	hemispherical.	flatter.
		brella smooth.
Width of disk in	85 to 100	100 to 300	1 60 to 200	70	200 to 300
mm.
Height of disk in	40 to 50	5°	50 to 100	30	ico to 150
mm.
Shape of marginal	All alike. Semicir-	Oval. The adradia	Kidney-shaped,	Lappets longer than	Tongue-shaped,
lappets.	cular.	clefts between	wider outward than	wide, triangular	narrower at base
		tentacular lobes are	at bases. The 16	with blunt points.	than beyond this
		deeper than others	ocular lappets		point. All of equal
		causing general	wider and longer		size. When old,
		outline of each	than the 16 tentac-		the 16 ocular lap-
		octant to be convex	ular lappets.		pets develop side
					lappets as in
					Dactylometra.
Shape of the 8	All 16 radial-	Ocular pouches are	Ocular stomach-	Twice as wide in	Ocular and tentacu-
ocular stomach-	pouches of equ 1	in middle twice as	pouches spindle-	middle; at margin,	lar pouches of simi-
pouches.	width in middl .	wide, at the mar-	shaped. In middle	half as wide as	lar form and size.
	At margin ocul r	gin half as wide,	as wide as tentacu-	tentacular pouches.
	are only half a	as tentacular	lar pouches.
	wide as tentacul r	pouches.
	pouches.
Shape of curtain-	Curtain-like, folded.	Lancet-shaped, in	Curtain-hke, very	Curtain-like. In	Tapering from a
like lips.	In middle as wide	middle two-thirds	wide and long.	middle as wide as	wide base to
	as radius of um-	as wide as disk-		radius of umbrella.	pointed ends. In
	brella.	radius. Margin			middle one-third r
		complexly folded.			wide. Margins
					much folded.
Length of mouth-	y	4r	6 to 8r	V	zr
curtains (lips) in
terms of disk-					'
radius r.
Length of longest	2r	Flat, ribbon-like, qr	Ribbon-like at their	?	Ribbon-like r-
tentacles in terms		long.	bases 2r-
of disk-radius r.
Color.	Bell rusty-yellow.	Bell and lips light	Ground color of um-	?	Bell, mouth-arms,
	Mouth-arms color-	yellowish-brown,	brella bright red-		and tentacles light-
	less, with yellow	with marginal lap-	dish-yellow, with a		bluish. 32 star-
	red.	arms speckled with	brown star on ex-		exumbrella. 16
		rusty-red . Tenta-	umbrella. Lappets		dark-brownish to
		cles dark rusty	brown. Mouth-		black radial streaks
		color.	arms yellow,		on subumbrella in
			spotted with brown.		radii of 16 lateral
			Gonads yellow.		tentacles. Gonads
					reddish-brown.
Where found.	West Coast of South	North Pacific Ocean.	Indian Ocean to	Southern parts of	North Pacific. Asia
	America. Cape	Asia to California.	east coast of Africa.	the China Sea.	to California.
	Horn to Peru.

*This species shows a tendency to approach the Dactylomctra stage in having 48 marginal lappets, but the tentacles remain 24 in number as in other species of Chrysaora. L. Agassiz, 1861, calls this Melanasler mertensii.

medusa is highly variable in color, sometimes pale, nearly uniform, milky ocher-yellow, and at other times with radiating streaks of rich red-brown.

The medusa is locally common but rare in many other places, such as Naples, where it is hardly ever seen.

According to Graeffe, C. hysoscflla is found at Trieste, Adriatic Sea, from November to April, and is mature in winter. It is hermaphroditic, and the eggs segment in the ovaries and are set free as pear-shaped planulze in March and April. At the end of 8 to 14 days they become attached by the broad anterior end and finally acquire 16 tentacles in the scyphostoma-stage. These strobilate in September and October and each gives rise to 8 to 12 ephyrae.

SEMAEOSTOME^E — CHRYSAORA. 581

Miss M. J. Delap finds that the scyphostoma of Chrysaora does not eat copepods or small fish, but feeds voraciously upon hydromedusx, siphonophorae, ctenophorze, and pelagic worms.

Claus, 1877, has studied the growth of the ephyra. At first the 8 ephyra lobes are very long and slender with deep, adradial clefts between them and with sharp-pointed, marginal lappets. There are 8 sense-organs but no tentacles. Later 4 and then 8 tentacles develop and the medusa is in the Pelagia-stage. The first 4 tentacles are in the 4 adradial clefts which precede the 4 perradii in the direction of the hands of the watch (see text-figure 372). The adradial stomach-pouches develop later than the perradial and interradial.

The hermaphroditism of Chrysaora was first observed by Derbes (1850, Annal. des Sci. Nat., tome 13, p. 377) and later by Wright (1861), Claus (1877), and Haeckel (1880). Young individuals are apt to be male, middle-aged ones hermaphroditic, older ones female. Some are, however, of one sex only throughout life. In other cases when the production ot e<i^ in the entoderm of the gonads begins to decline, a number of sac-like cavities, of irregular size, develop not only in the gonads but in other parts of the subumbrella wall, and these give rise

to spermatozoa.

Chrysaora hysoscella var. blossevillei.

Chrysaora blossevillei, LESSON, 1819, Voyage de la Coquille Zool., p. 1 15, planche 13, fig. 2; 1843, Hist.Zooph. Acalrplirs. p. 401 .— HAECKEL, 1880, Syst. dcr Mcdusen, p. ^14.— I-i N'UI NFJ LD, R. VON, 1884, Proc. Linncan Soc. New South Wales, vol. 9, p. 268 — VANHOFFEN, 1888, BiWiotlu-ca Zonlogica, BJ. i, Heft. 3, p. 15, taf. i, fig. 3.

Lobocrocis blossevillei, ACASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 166.

This is closely allied to C. h\<soscclla, of which it is probably a local variety.

Disk 28 to 37 mm. wide, or larger, and about 7 to n mm. thick. Kxuinbrella covered with small, round, nettling warts. According to VanhofFen there are 4 marginal lappets in each octant between successive sense-organs. The 8 interocular clefts are twice as deep as are the 16 clefts adjacent to them. The longest tentacles arise from the interocular clefts. These are about as long as bell-radius. The 2 other tentacles in each octant are only half as long as the interocular tentacles. There are thus 24 tentacles, 32 lappets, and 8 marginal sense- organs. 1 6 radial pouches extend out from the central stomach and these are twice as wide at margin in the interocular as in the ocular radii. The palps are shorter than bell-diameter. Bell and palps yellowish, speckled with rusty-red. Coast of Brazil. Best description by

VanhofFen.

Chrysaora hysoscella var. fulgida.

Rhizostama ful^idum, REYNAUD, 1830, Lesson's Ccnturie Zoologique, p. 79, plate 25.

Chrysaora julgida, HAECKEL, 1880, Syst. der Medusen, p. 514— VANHOFFEN, E., 1902, \Visscn. F.rgcb. deutsch. Tiefsee Expedi- tion, Valdhia, Bd. 3, Lfg. I, p. 38.

See synoptic table of forms of Chrysaora.

This form is very imperfectly known and may be identical with C. hysoscella. It is found off the Cape of Good Hope, Africa.

Chrysaora blossevillei var. plocamia.

Cyanea plocamia, LESSON, 1829, Voyage de la Coijuille Zool., p. 116, plate 12, figs. I, 2.

Chysaora plocamia, HAECKEL, E., 1880, Syst. dcr Medusen, p. 516.— VANHOFFEN, 1888, Bibliotheca Zool. Bd. !, Heft. 3, p. 16.

See synoptic table of forms of Chrysaora.

This form is found on the South Pacific coast of South America from Peru southward, and is allied to C. lilnss<-cill?i of the Atlantic side. Its marginal lappets are said to he semi- circular instead of oval as in C. blossevillei, and the contour of the bell-margin is circular, not octangular with concave inter-rhopalar sides. It is only misleading to attempt to separate species upon distinctions such as these.

Chrysaora helvola Brandt.

Chrysaora (Polybostrycha) hehola, BRANDT, iS-,8, M.:m. Acad. St. Petersbourg, Sci. Nat., ser. 6, tomr 4, p.-,S4, taf. 15, fign. 1-4. Chrysaora hehola, HAECKEL, 1880, Syst. der Medusen, p. 515.— VANHOFFEN, 1906, Nordisches Plankton, Nr. 11, p. 48, fig. n. Chrysaora convoluia, KISHINOUYF, 1910, Journal College of Sci. University Tokyo, vol. 17, art. 9» P- "• Platr 2- fiRs- "-'4-

See synoptic table of the species of Chrysaora.

Distinguished by the considerable length of the 16 ocular lappets, which project beyond the zone of the velar ones, thus giving an octangular appearance to marginal outline of bell. The medusa is found in the North Pacific from Asia northward to Alaska and eastward to the coast of California. Kishinouye finds that young cod are often found under the bell of

582

MEDUS.E OF THE WORLD.

this medusa. He gives good figures of it showing the considerable depth ot the adradial clefts between the lappets.

Chrysaora helvola var. calliparea.

(?) Cyanea calliparea, REYNAUD, 1830, Lesson's Centime Zoologique, p. 67, planche 20. Chrysaora calliparea, HAECKEL, 1880, Syst. der Medusen, p. 516.

See synoptic table of forms of Chrysaora.

This medusa is reported from Pondichery and Zanzibar, and our knowledge of it is still imperfect.

Chrysaora helvola var. chinensis.

Chrysaora chinensis, VANHOFFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 16.

In the single specimen described by VanhofFen the disk is 70 mm. wide and 30 mm. high. Exumbrella thickly covered with numerous, very small warts arranged in a scale-like manner from summit to margin. Ocular and tentacular marginal lappets of equal width and length, longer than wide, and each one ends in a blunt point; lappets overlap each other on their sides and this causes the ocular lappets to appear smaller and sharper than the tentacular lappets. The 16 radiating stomach-pouches are all of equal width at periphery of central stomach. The septa bordering the 8 ocular pouches trend so as to become wider apart for the proximal three-fourths of their lengths, so that the ocular pouches are about twice as wide as the tentacular ones at this zone. The septa then trend toward the ocular radii so that at

the bell-margin the 8 ocular stomach- pouches are only half as wide as the 8 tentacular ones. The 4 lips, or palps, are each 7 times as long as the radius of the disk. Near the mouth-opening they are almost as wide as bell-radius and are curtain-like. Midrib of each mouth-arm well developed, the folded margins thin. Outer parts of palps about one-third as wide as bell-radius, not tapering outwards, but ending bluntly. Color (?) Gonads (?) Tenta- cles (?) Found near Hongkong, China, in October.

This form is distinguished by its

FIG. 366. — Chrysaora helvola, according to Brandt, after Vanhoffen, in Nordishes Plankton.

peculiar exumbrella warts and its very long mouth-arms. It is separated from Chrysaora calliparea by its long, pointed, marginal lappets.

Chrysaora melanaster Brandt.

Chrysaora melanaster, BRANDT, 1838, Mem. Acad. Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 385, taf. 16, 17. — HAECKEL, 1880, Syst. der Medusen, p. 515. — FEWKES, 1889, Bull. Essex. Inst. Salem, vol. zi, No. 7, p. izi. — VANHOFFEN, E., 1906, Nordisches Plankton, Nr. n, p. 49, fig. 12.

Mclanailer menensii, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 126, 166.

Melanaster, sp., AGASSIZ, A., 1865, North Amer. Acal., p. 50.

See synoptic table of species of Chrysaora.

This abundant North Pacific form is found from Kamtschatka to California. Bell with reddish-brown radial lines extending from center to margin. Marginal sense-organs bright yellow and brown. Tips of tentacles are red. When old it develops 48 lappets, but the tentacles remain 32.

It is closely allied to Dactylometra quinquecirrha of the North Atlantic, and C. gilberti is one of its varieties.

Chrysaora melanaster var. "gilberti" Kishinouye.

Chrysaora gilberti, KISHINOUYE, 1899, Zool. Anzeiger, Bd. 22, p. 44, I fig.

Distinguished by its semicircular lappets all similar each to each and its relatively long tentacles. It is probably only a variety of C. melanaster.

SEMAEOSTOME.E — CHRVSAORA, DACTYLOMETUA.

r,s:;

Umbrella 70 to 100 mm. wide, 25 to 30 mm. high. Exumbrella thickly besprinkled with nematocyst-warts. 32 marginal lappets, all similar each to each and all nearly semicircular. 24 laterally compressed tentacles, all somewhat longer than bell-diameter. The 4 subgenual ostia are round to oval. The septa between the 16 radial stomach-pouches are nearly straight, but the ocular pouches are a little broader than the tentacular pouches at the annulus of the marginal sense-organs. The 4 oral curtains are as broad as the bell-radius near the mouth and are very long with finely frilled margins. In contraction they are coiled, screw-like; and in this condition are about as long as bell-radius. They taper to blunt points and their thick proximal parts are covered with nettle-warts.

Umbrella light brown, tentacles and midrib of mouth-arms darker brown. Common in Monterey Bay, California, in summer.

Genus DACTYLOMETRA L. Agassiz, 1862.

Dact\lomelra, AGASSIZ, L., 1862, Cont. Nat. Hist. U.S., vol. 4, p. 166. — AGASSIZ, A., 1865, North Amer. Acal., p. 48.— HAICKEL, 1880, Syst. der Medusen, p. 517. — KISHINOUTE, 1892, Zoological Mag., Tokyo, vol. 4, p. 261. — AGASSIZ AND MAYER, 1898, Bull. Mus. Comp. Zool. at Harvard College, vol. 32, p. [. — VANHOFFEN, 1902, Wissen. Ergeb. dcutsch. Tiefsee Expedition, Dampfer I'aldiria, Bd. 3, Lfg. I, p. 39; 1906, Xordisches Plankton, Nr. 1 1, p. 50.

The type species is D. lactca L. Agassiz, of the West Indies and South American coast.

GENERIC CHARACTERS.

Pelagidae with 40 tentacles, 5 be- tween each successive pair of sense- organs, and with 48 marginal lappets.

Fir.. 367. — Chrysaora melanaster, according to Brandt, after Vanhoffen, in Nordisches Plankton. FIG. 368. — Chrysaora gilberti, after Kishinouye, in Zool. Anzeiger.

There is reason to believe that certain medusae may become mature with 24 tentacles, while others, possibly better fed individuals of the same species, may develop 40 tentacles before becoming mature. Similarly Dactvlometra longicirra of Japan may develop 40 or even 56 tentacles before becoming mature. The conditions characteristic of the genera Chrysaora, Dactylometrti, and Kuragea may therefore be transitional stages in the growth of one and the same medusa.

584

MEDUSAE OF THE WORLD.

Mature medusa. — Bell hemispherical, smaller than in D. quinquecirrha being about 70 mm. in diameter. Clefts in lappets adjacent to sense-organs fully as deep as those between the remaining lappets instead of being mere shallow notches, as in D. quinquecirrha. The tertiary tentacles arise from clefts between the lappets, not from the floor of the subumbrella, as in D. quinquecirrha. The 8 primary tentacles are about 3 times as long as the bell-diameter. The 16 secondary tentacles, however, are only about half, and the 16 tertiary, one-quarter as long as the primary ones.

General color dull milky-white, exumbrella sprinkled over with ocher-yellow-colored spots, thickly clustered at aboral pole. Genital organs slightly yellowish, a delicate irides- cence over the long, flexible mouth-arms.

FIG 369. — Daetylemetra lactea, aboral view, three-fourths natural size. From nature, by the author. Showing variable character of the lobes and tentacles.

In Havana

This species is found at Rio Janeiro, Brazil, and at Jamaica and Cuba. Harbor it is abundant and mature in February.

A mature specimen found by me off Port Royal, Kingston Harbor, Jamaica, on March 20, 1909, was of the following dimensions in millimeters: Bell 66 wide, somewhat flatter than a hemisphere, palps 50, longest tentacles 60 long. Exum- brella regularly and thickly besprinkled with very small, low- lying, milky-yellow colored netthng-warts. 16 spoke-like stripes of dull ocher color and numerous russet-brown nematocyst-warts at the margin of the exumbrella. Gelatinous substance and ten- tacles milky. Gonads dull milky-pink. This specimen was very irregular in the development of its tentacles and lobes, the 8 octants being as shown in the table (fig. 369).

Octant No.	No. of tentacles.	No. of lobes.
1	3	4
2	4	4
3	5	5
4	8	7
5	4	5
6	3	3
7	3	2
8	4	4

PLATE 62.

Fig, I. Dactylometra quinrjuecirrha, natural size. In the "Clirysaora " stage.

From the brackish water of the St. Mary's River, Chesapeake

Bay, Maryland, November 13, 1905. Fig. 2. Dactylometra quinquecirrha, natural size. In the " Chrysaora" stage.

Agassiz Laboratory, Newport, Rhode Island, August 2, 1892.

Drawn from life, by the author.

MAYER

PLATE 62

PLATE 63.

Dactylometra quinquecirrha, natural size. Mature in the "Chrysaora" stage, in the brackish water of Norfolk Harbor, Virginia, November 4, 1904.

Drawn from life, by the author.

MAYER

PLATE 63

PLATE 64.

Mature Dactylometra quinquecirrha, half natural size. Highly-colored, mature specimen from Tiverton, Narragansett Bay, Rhode Island. September, 1896.

Drawn from life, by the author.

fLATE 64

PLATE 64A.

Dactylometra quinquecirrha, drawn by the late Prof. William K. Brooks from a specimen obtained at Beaufort, North Carolina.

•-

PLATE 64A

SEMAEOSTOME*: — DACTYLOMETRA. :,s.-,

Dactylometra quinquecirrha L. Agassiz. Plates 62 to 64A.

Ptlagia quinquecirrha, DESOR, E., 1848, Proc. Boston Soc. Nat. Hist., vol. 3, p. 76.

Dactylomtlra quinquecirrha, AGASSIZ, L., 1862, Cont. Nat. Hist. V. S., vol. 4, pp. 115, 166.— AGASSIZ, A., 1865, North Amer. Acal., p. 48, fig. 69.— HAECKEL, 1880, Syst. dcr Meduscn, p. 518. 1 MVKS, 1882, Bull. Mus. Comp. Zool. at Harvard College, vol. 9, No. 8, p. 293, plate i, figs. 25-28, 38, 39— BICELOW, 1890, Johns Hopkins I'niv. Circul., .... 80,

p. 65.— AGASSIZ, A., AND MAYER, 1898, Bull. Mus. Comp. Zool. at Harvard College, vol. 32, p. i, plates 1-1 1, 33 figf.— HARGITT, 1904, Bull. U. S. Bureau of Fisheries, vol. 24, p. 69, plate 7, fig. 2. HAR'.irr, 1905, Journal Eiper. Zool., vol. 2, p. 575 (variations).— VANHOFFEN, 1906, Nordischcs Plankton, Nr. 11, p. 50, fign. 13-14.

Bathyluca Solaris (damaged and regenerating specimen?), MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard College, p. i, plate i.

Cbrysaora, BIOELOW, R. P., 1880, Johns Hopkins Univ. Circulars, vol. 9, No. 8, p. 66 (brackish-water variety from Chesapeake Bay).

Adult medusa. — Bell nearly hemispherical, 170 to 190 mm. in diameter. Numerous small, wart-like clusters of nematocysts thickly scattered over the exumbrella, especially abundant at aboral apex where they appear as little hemispherical projections above tlu general surface; near the margin they are elongate in shape, while at the margin itself they

. 370. — Dactyhmrtra laclea from Havana, Cuba; after Agassiz and Mayer in Bull. Mus. of Comp. Zool.

A, side view; B, oral view.

are again hemispherical as at the apex. 8 marginal sense-organs, 40 tentacles, and 48 marginal lappets. The marginal sense-organs are set within niches between the lappets, 4 bung pii- radial in position and 4 interradial; these niches are protected above by a small web bet \M-I-II the lappets. A ciliated, pit-like depression extends downward from the suil.ni of the ex- umbrella immediately above each sense-organ. The sensory-club projects slightly down- ward and contains a distal, entodermal mass of crystalline concretions but no ocellus. The entodermal core of the sense-club is hollow and its lumen is connected with the general gastrovascular space of the medusa.

There are 5 tentacles between each successive pair of sense-organs. 3 of these tent.n les, the primary and secondary, arise from the clefts between the lappets, but the other 2 (terti.irv > are generally found to spring from the under or subumbrella side of the ocular lappets; for even in very large medusae the ocular lappets exhibit but a slight notch adjacent to the ter-

586

MEDUSAE OF THE WORLD.

tiary tentacles; in fact, the tertiary tentacles do not usually make their appearance until the medusa is about 130 mm. in diameter and the lappets remain undivided until the medusa is mature, although Hargitt shows that this is subject to great individual variability. Thus in immature medusae of large size there are usually but 24 tentacles and 32 marginal lappets, and the animal is in the "Chrysaora stage." I believe, also, that they often mature in this stage and never reach the Dactylornetra condition.

The primary and secondary tentacles are very long and flexible while the tertiary ten- tacles are only a few millimeters in length. In like manner the lappet-clefts of the primary and secondary tentacles are deep and the lappets almost as long as they are broad; while the lappet clefts of the tertiary tentacles are mere shallow notches in the contour of the lappets adjacent to the sense-organs. Mouth-opening cruciform, in center of subumbrella, at extremity of a 4-cornered oesophagus and surrounded by 4 mouth-arms or palps, which when fully extended are about 3 or 4 times as long as the bell-diameter. The 8 free edges of the mouth- arms are complexly crinkled and highly flexible. The central stomach occupies a wide lentic- ular space in the midst of the bell and gives rise to 16 simple, radiating pockets, 8 in the tentacular and 8 in the rhopalar radii. These pockets are completely separated one from another by 16 radiating septa which join the upper and lower walls of the umbrella cavity

together. The tentacles are hollow throughout the greater part of their length and their entoderm is ciliated as is that of the stomach itself.

The gonads are contained in 4 interradially situated, entodermal in- foldings of the wall of the subum- brella, and their position is marked by 4 deeply sunken, subgenital pits. The genital organs are provided with numerous, simple, unbranched gastric cirri which project inward into the stomach-cavity. There are two sets of radial muscle-fibers; the principal set is found in the 16 septa between the gastric pouches, and alternating with these in position are 16 strands in the exumbrella, 8 of which lead outward to the sense- organs and 8 to the primary tentacles. Color quite variable. In some individuals the disk is pink, in others yellow with a bluish opalescence. The exumbrella is thickly sprinkled with yellow-ocher colored nettling-warts and there are 16 radiating stripes of reddish color upon the exumbrella in the radii of the septa of the peripheral stomach. These reddish stripes extend about half-way from the bell-margin toward the center of the exumbrella and are due to highly refractive, rosin-colored pigment granules within the epithelial cells of the disk. The male gonads are generally pink, while the ovaries are yellowish or ashy-gray. The radial muscle-strands of the subumbrella are of a glistening white and the entodermal cores of the tentacles are pink. The mouth-arms are pink or yellow and always sprinkled over with red-colored pigment spots. The marginal sense-organs contain each a mass of glistening white concretions, but no ocelli. This species extends from the southern coast of New England to the tropics. In August it is abundant in Tampa Bay, Florida. It has been taken by Bickmore at the Bermudas, and by Drayton between the Bermudas and the Azores. "A well-marked southern variety" was found by Brooks at Beaufort, North Carolina, and is figured in plate 64A. It makes its appearance upon the surface along the coast of New England in August when large medusae are found. The young rarely come to view, but remain in deep water.

Varieties and development. — The egg develops into a free-swimming planula which soon attaches itself to the bottom and develops into a scyphostoma having normally 4 ten-

FIG, 371. — Dactylometra quinquecirrha, after Agassiz and Mayer, in Bull. Mus. of Comparative Zoology at Harvard College.

SEMAEOSTOME^E — DACTYLOMETRA.

587

tacles. R. P. Bigelow, 1880, states that the so-called " Chrysaora " of the Chesapeake, which is only a brackish-water, abortive variety of Dactylometra, develops trom an ephyra through a Pelagia stage, wherein it has only 8 tentacles and 16 lappets, and Brooks has figured the ephyrae in the text figures here shown.

The present writer found considerable numbers of Chrysaora-like medusae in Hampton Roads and Norfolk Harbor, Virginia, and in St. Mary's River, Maryland, early in Novem-

FIG. 372. — Young ephyra of Daclylametra quinquccirrha. Figures drawn by the late Prof. William K. Brooks at the Chesapeake Bay Laboratory of the Johns Hopkins University. Presented by the Department of Biol- ogy of the Johns Hopkins University for publication in this work.

ber, 1904 and 1905. These were generally pale milky-yellow in color and lacked the rich brown pigment and the 16 pigmented, radial areas seen upon the exumbrella of Dactylometra fjuinrjufdrrha. Others had a red-brown spot at the apex of the exumbrella, and surrounding this was a star-like zone of red-brown streaks with pointed ends directed outward. The

5ss

MEDUSAE OF THE WORLD.

axial ribs of the mouth-arms (palps) were red-brown. Although all were in the Clirysaora condition and had only 3 tentacles and 4 lappets in each octant, some appeared to be fully mature or with gonads nearly ripe. The exumbrella surface and the palps were covered with dull milky-yellow clusters of nematocysts. There were 8 marginal sense-organs as in Dact\lo>jietra, but only 24 tentacles and 32 marginal lappets. None of the medusae were, however, as large as is commonly seen in full-grown Dactylometra quinquecirrha, the largest Chrysaora-hke medusa seen in Norfolk harbor being only 105 mm. in diameter. It should be borne in mind that D. /jiiinquecirrha does not usually attain 48 marginal lappets and 40 tentacles until the medusa is 120 mm. in diameter, and it seems therefore that the so-called Chrysaora of the Chesapeake is only a stunted Dactylometra which becomes mature in the Chrysaora stage, and its pale coloration may be a local peculiarity due to unfavorable conditions of confinement in brackish water. In the purer ocean water at the mouth of Chesapeake Bay the medusae develop into the Dactylometra condition with 40 tentacles. These conditions are also found in Narragansett Bay, Rhode Island, where in relatively pure clean water the medusae have 40 tentacles, but in brackish estuaries they often become mature with only 24 tentacles and are pale in color.

FIG. 373. — Dactylometra ajricana, after Vanhbffen, in Valdlvia Expedition.

Dactylometra africana Vanhb'ffen.

Dactylometra afrifana, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Dampfer Valdivia, Bd. 3, Lfg. I, p. 40, taf. 4, fig. 20.

Disk 100 to 130 mm. wide. 6 well-developed marginal lappets and 5 long tentacles in each octant. Lappets and tentacles red. Red radial streaks over exumbrella. (Esophagus, palps, and gonads not highly colored. Colors of large specimens duller than those of small medusas and not unlike the coloration of D. quinquecirrha. Distinguished by its red lappets. Coast of German Southwest Africa. Common in the Great Fish Bay on October 10, 1898.

Dactylometra ferruginaster Kishinouye.

Dactylometra ferruginaster, KISHINOUYE, 1892, Zoological Magazine, Tokyo, vol. 4, p. 264, taf. 3.

Dact\jometra pacifica var. ferruginasttr, MAAS, 1909, Abhandl. Akad. Wissen. Munchen, Suppl. Bd. I, Abhandl. 8, p. 44, taf. 2, fig. 14.

Bell flatly rounded, 3 to 4 times as wide as high, 100 mm. in diameter. 48 oval, marginal lappets. The 8 primary tentacles longer than the others. The lappets next to the ocular

SEMAEOSTOME/E — DACTYLOMETRA, KURAGEA. 589

lappets are the smallest, and only about half as wide as the others. The 16 radial stomach- pouches of nearly similar form and size. Mouth-arms longer than hell-radius and tapering to pointed tips. Bell white with reddish-brown star on exumbrella. Inner sides of mouth- arms and tentacles brown. Found on the coast of Japan in autumn. This form is imper- fectly separated from D. quinqueeirrha of which it appears to be a variety, if, indeed, it be not identical with the American medusa.

"Dactylometra longicirra" Kishinouye.

Dactylomctra quinijuecirrha var. facifca, GOETTE, 1886, Sitzungsbcr. Akad. \Visscn. Berlin, Jahrgang 1886, p. 834. Dact\lomctra longifirra, KISHINOUYK, 1892, Zoological Magaiinc, Tokyo, vol. 4, p. 261, taf. z.

Bell flatly rounded, 3 times as wide as high and 75 mm. in diameter. 48 tongue-shaped marginal lappets, all similar each to each, somewhat narrower near their bases than near their outer ends. Accessory lappets sometimes seen on sides of ocular lappets. 40 tentacles of nearly equal length each to each, and 10 times as long as hell-diameter; these tentacles are wide, flat, and ribbon-like near their bases; sometimes one finds small accessor}' tentacles arising from between the ocular lobes and their accessory lateral lappets or from the sub- umbrella surface of the ocular lappets. The medusa then has 56 tentacles, 7 in each octant as in Ktiragca Jepressa of Japan, and this illustrates the close genetic relationship which exists between the two forms. In the middle the ocular stomach-pouches are twice as wide and in their distal parts halt as wide as the tentacular pouches. The mouth-curtains are very wide and much folded; they are about 5 times as long as bell-diameter.

Bell white with 32 reddish-yellow radiating streaks. Mouth-arms yellow. Gonads and tentacles reddish.

Found on the Pacific coast of Japan, in Owari Bay. Its common Japanese name is Aschinaga Kurage, or Akakurage. I am inclined to believe that this is only a growth-stage of Kuragea depressa, and that it is identical with D. ferruginaster.

Genus KURAGEA Kishinouye, 1902. Kuragca, KISHINOUYE, 1902, Journ. College Sci. Tokyo, vol. 17, art. 7, p. 9, plate I, 6g. 7.

The type species is K. depressa of Japan.

GENERIC CHARACTERS.

Pelagidae with 8 marginal sense-organs. 8X7 (56) tentacles. 8X8 (64) marginal lobes. 4 interradial gonads.

This genus bears the same relation to Dactylometra that the latter does to Chrysaora, being a stage wherein the lappets and tentacles have progressively increased by 16 in number.

Thus Chrysaora has 24 tentacles and 32 lappets, Dactylometra has 40 tentacles and 48 lappets, Kuragea has 56 tentacles and 64 lappets. I am inclined to look upon this form as an hypertrophic Dactylometra rather than as a separate genus.

Kuragea depressa Kishinouye.

Kuragea Jepressa, KISHINOUYE, 1902, Journ. College Sci. Tokyo, vol. 17, art. 7, p. 9, plate I, fig. 7.

Umbrella 85 mm. wide and 30 mm. high. 8 marginal sense-organs. 8X7 (56) tentacles.

8x8 (64) marginal lobes. 4 gonads, each folded in the form of the Greek letter «>. Gastric filaments long and numerous. Color (?) Misaki, Japan. A single specimen.

The 1 6 ocular lobes and the lobes by the sides of the adradial tentacles are larger than the others, while those adjacent to the ocular lobes are the smallest. The lips are broad and complexly folded. The exumbrella exhibits a i6-rayed, star-shaped marking in the inter-radii, adradn, and perradn. The central stomach gives

F,c. 374.-K*ratf. depwa, after Kishinouye, in Journal ™e tO ' 6 Peripheral pouches as in Dactylomctra

College of Sci., Tokyo University. longictrra. In the middle of their lengths the 8

590

MEDUSA OF THE WORLD.

rhopalar pouches are 1. 5 times as wide as the 8 tentacular pouches, but at the bell-margin only half as wide.

This medusa is clearly derived from Dactylometra longicirra of Japan. D. lactea of America tends to attain to the Kuragea condition, but all of the octants do not usually develop

equally (see text-fig. 369).

Genus SANDERIA Gbtte, 1886.

Sanderia, GOETTE, 1886, Sitzungsber. Akad. Wisscn. Berlin, Jahrg. 1886, p. 835. — VANHOFFEN, 1902, Wissen. Ergeb. deutsch.

Tiefsee Expedition, Dampfer, Valdtvta, Bd. 3, Lfg. i, p. 37. Xeopelagia (an aberration), KISHINOUYE, 1910, Journal College Sci. Tokyo, vol. 27, art. 9, p. 14.

The type species is Sanderia malayensis Goette, of the tropical Indian Ocean and Malay Archipelago.

GENERIC CHARACTERS.

Pelagidae with 16 marginal sense-organs, 16 tentacles, and 32 cleft marginal lappets. 4 lips, 4 interradial gonads, and 32 peripheral stomach-pouches in the radii of the tentacles and sense-organs. No marginal ring-canal.

Sanderia malayensis Goette.

Sanderia malayensis, GOETTE, 1886, Sitzungsber. Akad. Wissen. Berlin, Jahrg. 1886, p. 835. — VANHOFFEN, 1902, Wissen. Ergeb.

deutsch. Tiefsee Expedition, Dampfer Valdivia, Bd. 3, Lfg. I, p. 38, taf. 3, fig. 12; taf. 8, fign. 69-74. Ncopclagia eximia, KISHINOUYE, 1910, Journal College of Sci. Tokyo, vol. 27, art. 9, p. 14, plate 3, fig. 15, text-fig. I.

Bell flat, 90 mm. wide, large, rounded nettling-warts at the center of the exumbrella but diminishing in size outwardly so as to be absent at the bell-margin. 16 marginal sense-organs

FIG. 375. — Sanderia malayensis, after Vanhbffen, in Valdivin Expedition.

alternating with 16 long, ribbon-like tentacles, 32 cleft lappets. A long, tubular oesophagus is bounded on the 4 perradial corners by long, complexly folded lips. The 4 interradial, heart- shaped, genital ostia are each bordered externally by about 24 to 30 finger-shaped papillae. The central stomach gives rise to 32 peripheral pouches in the radii of the sense-organs and tentacles. These are completely separated one from another by straight, radiating septa which converge slightly near the bell-margin in the rhopolar radii. There is no marginal ring-canal. The gen- eral color is yellow with the aboral center of the bell dusted over with reddish flecks which extend outward, spoke-like, in the radii of the sense-organs and tentacles. The mouth-parts are also covered with reddish spots.

S KM. \KOSTOMK.K — SANDKUI A , I)KSM( )X KMA. .V.ll

Found in the Indian Ocean, Gulf of Aden, at Singapore, and off the east coast of Africa. Some specimens of this medusa were found by the U. S. Fisheries Bureau Steamer .ll/mtross in the Philippine Islands in March and April, 1908, and Kishinouve found it at Misaki, Japan.

A perfect specimen found by the Albatross on March 8, 1908, at station D 5175 in the Sulu Sea, southeast of Cagayanes Islands, Philippine Islands, had a bell 75 mm. wide, palps 4(1 long, central stomach 35 wide, contracted tentacles 65 long, and with 25 to 30 finger-shaped pro- jections bordering each genital ostium.

Kishinouye, 1910, found an abnormal specimen with 13 tentacles, 13 rhopalia, 2(1 lappets and irregularly developed gonads. He found that a fish of the genus Psenes accompanied the medusa.

Family CYANEIDjE L. Agassiz, 1862.

Cfane'uLt, AC.ASMZ, L., 1862, Cunt. Nat. Hist. I'. S., vol. 4, pp. 114, 161. — AGASSIZ, A., 1865, North Amer. Ac.il.. p. 44.

HAECKEL, 1880, Syst. der Medusen, p. 518; 1881, Challenger Report, /.<>.,!., lid. 4, part, i, p. 124.— Cl AI -. i v\;, ( >rgan. und Entwick. Medusen, p. 24. — VON LKNDENFELD, 1884, Proc. Linnean Soc. NVv, South \\.il-s, vol. 9, p. 271. — CIAI S, 1886, Arbeit. Zool. Inst. Univ. Wicn., Bd. 7, p. no. — VANHOFFEN, 1906, Nordischcs Plankton, Nr. n, p. 51.— MAAS, 1906, Fauna Arctica, Bd. 4, Lfg. 3, p. 505.

FAMILY CHARACTERS.

Semaeostomes with a single, 4-sided, central mouth surrounded In 4 perradially situated, curtain-like lips. The tentacles arise from the floor of the suhumbrella. at some distance inward from the margin, and are usually in clusters. The gonads are situated in 4 complexly folded, imerradial outpocketings of the wall of the subumbrella. The central stomach gi\cs rise to radiating, peripheral pouches, which in turn give rise to numerous branching, non- anastomosing, blind canals in the lappets. There is no ring-canal. The tentacles are hollow.

The medusae of this family are apparently descended from some such forms as the Pelag- idas. They resemble the Pelagida; in the structure of the oral appendages, the general plan of the gastrovascular system, and in the lobulation of the bell-margin. They differ mainly in the complex branching of the peripheral edges of the radiating stomach-pouches, and above all in that the tentacles arise from the floor of the subumbrella, not from the notches between the lappets as in the Pelagidse. The young medusie are strikingly similar to tin- Pelagidae in all respects, for their radiating stomach-pouches are simple and the tentacles first appear in the notches between the lappets. The margin grows beyond the bases of the tentacles as development proceeds, however, and thus they come secondarily to arise from the floor of the subumbrella. Indeed the tentacles of all Scyphomedusae are structures of the subumbrella.

In ('.\nncn the development is known to be through a sessile sc\ phustnnia which strobi- lates, giving off a number of ephyrae which develop into mature imilus;e. The Cyaneidae are of universal distribution, but the great majority of the species are found in the temperate regions and in the colder waters. Unlike the Pelagidae the Cyaneidae are creatures of the shallower waters along shores, not animals of the high seas.

A synopsis of the genera of the Cyaneidas follows:

Desmonema L. AUASSIZ, 1862. 8 rhopalia, 8 adradial clusters of tentacles. No radial-muscle strands in the subum- brella.

C\anea PEK»\ tr l.isrn-R, 1809= Proc\anea+ .WeJara + Strnopl\chajr- Deitnontma (in part) * (.•'.. HA£Clcrt,l88o. S rhopalia, 8 adradial clusti'i of tentacles; each cluster contains several rows of tentacles. Both radial and circular muscles in the subumbrella.

Dr-imonema HAECKEL, 1880. 8 rhopalia. Tentacles not grouped in isolated clusters, but arising from a wide zone in the subumbrella.

( ?) Patera LESSON, 184', (doubtful). 16 rhopalia. 16 clusters of tentacles alternating with the radii of the rhopalia.

Genus DESMONEMA Agassiz, 1862.

Couthouvia, used for Mollusca by Adams. lS(,o, Ann.il. and Mag. Nat. Hist., vol. 5, p. 410.

Couthouyia, AGASSIZ, L., 1862, Cont. Nat. Hist. I". V, \.<1. 4. pp. 118, 163.

Couthouya, Maas, 1906, Fauna Arctic.). B I. 4. l.tr. -,. pp. 487, 505; 1908, Eipedition Antarctiquc Franchise, Meduscs, p. 3.

Desmonema, AC.ASM/. I... [861, l'..nt.\at. Hi-t. I . S.. vol. 4, p. 166.— HAECKEL, (in part), iSSo, Syst. dcr Mcdusrn, p. 526. — LENDENFELO R.,V,.N.. |S*4, Pr.ic. Linnean Soc. New South Wales, vol. 9, p. 273. V*N H..t FEN, 1888, Bibliothcca Zoo- logica,BJ. I, Heft. 3, p. 17.— BROWNE, 1908, Trans. Royal Soc. Edinburgh, vol. 46, p. 24;. VANRorriN, njos. [Vutsche Sudpolar Eiped., Bd. 10, Zool. 2, p. 40.

Meiiora (young stage), AGASSIZ, L., 1862, C..MI. Nat. Mi,i. I S.. \,,1. 4, p. n8.

Medora, preoccupied for Mollusca by Adams, 1858, (ienrra of Mollusca, vol. 2, p. 183.

592

MEDUSA OF THE WORLD.

GENERIC CHARACTERS.

Cyaneidae with 8 marginal sense-organs and with 8 adradial clusters of marginal tentacles. The tentacles of each cluster may arise in several rows from the subumbrella surface. There are 8 chief lobes and 16 to 32 secondary lappets. Without radial-muscles in the lobes.

Thenames Couthr,u\in andMedora are preoccupied, but Agassiz'sDesinvnt-mii may be used.

The oldest species is the little-known "Chrysaora" gauJichaudii erroneously described by Lesson, 1829 (Voyage de la Coquille, Zooph., p. 1 14), from the region of Cape Horn, South America, and recently revealed through the studies of Maas, 1908.

Some of the medusae which Haeckel included in his genus "Desmonema" represent only immature Cyaneas in which the tentacles of each cluster arise in a single row. Vanhoffen, 1888,

FIG. 376. — Desmonema gaudichmtdii, after Maas, in Meduses Expedition Antarcticque Franc-aise.

shows, however, that there are considerable anatomical differences between Cyanea in any stage and Desmonema. In Desmonema, for example, the 8 clusters of tentacles arise in linear arcs concentric with the general contour of the bell-margin, whereas in Cyanea they arise in crescents, the horns of which are directed outward toward the margin. Moreover, there are no radial-muscle strands in the 8 velar lobes of Desmonema, but these are found in Cyanea.

Desmonema annasethc Haeckel is clearly a young Cyanea, as was pointed out by Van- hofFen, 1888.

The rediscovery of Lesson's, Cape Horn, medusa by Maas makes it practically certain that it is specifically referred to by Agassiz, 1862, p. 118, under the designation Coiithouyia pcndula.

SK.MA KdSTnMK.K HKSMiiNKMA. .V.l.'l

Demonema gaudichaudii Agassiz.

Chrysaora gamin liauilii, 1. ISMJN, iS-ij, Voyage de la Co/juille, Zooph., p. 114, Zoophytes planchc 13, fig. I.

Couthou \ia pendulti atul Mtdora eapfn: . \,\- [/, I.., i X*.:, r>.nr . \.ii. Hi '. I . S.j '-»!.4, pp. 118, !'>;.

I)eimantma gaudichaudi, AGASSIZ, L., l86i, Coin. Nat. Hi '. I". S., vol. 4, p. ifcG. — H\i< mi., 1880, Syst. dcr Mcdusen. p. 527.

Couthouya gauji<hautli, MAAS, iqoS, Kxprd. Antarctique Francaise, Meduscs, p. 5, planclie i, 6g. I.

Bell at least 500 or 600 mm. wide, only 5 to 7 tentacles in a single line, in each intcr- rhopalar cluster. Thus when the medusa is of a greater size than I), chierchiana, if has fcwei tentacles. Maas states that the color of the gastric cavity is brownish-purple, accentual < il in the gonads, while the muscle-system is lighter and the gelatinous substance is bluish and transparent. The medusa is found in the Antarciic region in April. Future studies will probably demonstrate that /). cliifrcli'uina is onlv a variety of this medusa for they are alike in all respects excepting that in Desmonema chierchiana the tentacles arise in several rows, whereas in /). gaudichaudii they remain as a single row even when the medusa is much lai than I), chierchiana. This difference may be due to environmental causes, or mav be of the nature of a variation such as one observes in the development of tentacles in J)<ict\lrjtn,-tni and Chrysaora, but until further studies have been carried out it will be safer to keep the two forms specifically distinct one from the other. It is probable, however, that f). yamii- i-liiiuiln is only a variety in which the tentacles remain in a single row, as in the \IUIIIL: <>t I). chierchiana (see fig. 37'' L

Further details of the structure of D. gaudichaudii may be obtained from the description ot J). chierchiana which follows.

Agassiz's Medora i-iip,-n.\i.\ is apparently a young stage of this medusa.

Desmonema chierchiana Vanhbffen.

Dcsmonema chierchiana, VAMHH i i .. iSSS, Bibliotheca Zoologica, Bd. i, Heft }, p. 18, taf. I, fig. 4; 1908, Deutsche SiidpiJ.ir Expedition, 11)01-11)05, Bd. 10, Zonl. 2, p. 41, taf. 2, fign. 2, 3; Abbild. 5-9.— BROWNE, 1908, Trans. R..yj| Sue. Edinbm vol. 46, p. 244, plate i, fig. 2.

( ? ?) Chrysaora gaudichaudii, LESSON, 1829, Voyage de la Co^uillft Zooph., p. 114, planche 13, fig. i.

Umbrella ^10 mm. or more wide and loo mm. high. Exumbrella smooth. The 8 pairs of ocular lappets are onlv about one-third as wide as the S tentacular lappets, which are flatter than a semicircle in outline. The 16 small, ocular lappets are bluntly rounded and sharply set off from the 8 tentacular lappets. The subumbrella is divided into id equal sectors cor- responding to the id stomach-pouches. These sectors are areas in which the circular muscles are well developed and separated one from another by narrow septa. 8 of the id muscular sectors are in the radii of the SI marginal sense-organs and 8 are intermediate. There aie no radial-muscle strands.

There are 8 groups of tentacles, each of which, in old medus:e. arises in several rows from the subumbrella at some distance inward from the bell-margin. These tentacles are developed along the outer edges ot the X interocular. circular muscle-sectors. There ai. about do tentacles in each cluster, the oldest and longest being along the innermost, and the shortest and youngest in the outermost rows. The lows are not U-shaped, as in Cyanea, but are nearly straight. The tentacles are hollow, their entoderm being thin and the ectoderm thick-walled. When voting the tentacles are somewhat flattened and the ectodermal longi- tudinal muscle strands are set within infolded, Butter-like lines down the length of the ten- tacle. As growth proceeds these gutters sink deeper and deeper into the ectoderm and finally become inclosed tubes, sunken beneath the surface. Thus the longitudinal muscles become tubular strands of fibers. A full description of the tentacles is <M\CII by Vanhoffen, i,>o8. \\hen expanded the tentacles of a large medusa may be at least 20 meters Ion;;.

The 4 mouth-curtains are well-developed and resemble those of ('.lir\><i'>r<i. The}' are narrow near the mouth-opening but expand outwards and then taper gradually to a point. Each mouth-curtain is i.« times as Ion;: as the bell-radius and its martinis are much folded.

J !"> D

The 4 sac-like, protrusive gonads are folded and resemble those of (.' \',nii-/i, but are smaller. There are 16 sectors ot circular muscles in the subumbrella. S in the ocular and S in ihe interocular radii. These circular muscles do not extend beyond the zone of the clusters of tentacles and sense-organs and are not found in the subumbrella of the lappets. There an no strands of radial-muscles in the subumbrella, or in the lappets, such as are seen in (* \-iiu.

594

MEDUS.E OF THE WORLD.

The 16 stomach-pouches break up into numerous forked, branched, radiating vessels in the marginal lappets, hut their ultimate branches rarely anastomose. There are about 12 to 1 8 main branches from the outer edge of the stomach-pouch in each lappet and these branch dendritically so that about 100 ramuh reach the bell-margin. There is no marginal ring-canal.

FIG. 377. — Desmonetna chierchiana, after Vanhoffen, in deutsch. Siidpolar Expedition.

The medusa is salmon-red or brownish-red, the canal-system being darker and the tenta- cles light in color. When young the bell and tentacles are bluish and the curtain-like lips salmon or brownish-red in color.

8EMAEOSTOME i: DE8MONEMA, CTANEA.

595

1 he medusa appears to lie common trom December to June in the Antarctic region, ami is reported I'rom Imth sides of the Straits of Magellan, KciiMielcii. and the Falkland Islands; and from Kaiser \\ ilhelm Coast, South Victoria and Alexander I Land along the ice-edge ot the Antarctic continent.

Ephyrae ^ to IO mm. \\ule are tound in January and February, and Vanhiitten records a young medusa in the M.Jara stage Irom Gauss Station, Kaiser \\ ilhelm Land on April 14. This medusa was }S mm. in diameter, the mouth-arms 10 mm. long. There were 8 principal tentacles about two-thirds as long as bell-diameter, and 4 of these were bordered on one side by a small tentacle ot recent development, figure ^~(). The lips and gastric cirri were brownish-red, other parts being translucent milky-blue. A later stage is descubed by Browne (see figuie $~H |.

Genus CYANEA P6ron and Lesueur, 1809.

C\,irii'<i, PV'.KIJX ASI> l.i M i i i:, 1809, Ann. Mir . Hi r. \,it. Paris, tome 14, p. 363. — EsCHtCHOLIZ, 1829, Syst. dcr Acalephrn, p. 67.— LiasON, 1843, Hist. Zooph.Acal., p. 379. BRAKDT,l838, •' •, Si ;. N.ii.. •• r. i>. tome

4, p. 77.— FORI:>-. iXjs. Itiitish X.iki-,|.i i i 1862, Cont. Nat. Hist. U. S., TO!. 4, pp.

Id I. An".-.!/. A., lXhv, \. ii lh ATI!, r. \i ,il.. p. 44.-- - VMS l.i MUSI I I I). |SS;, 7j-\\ . fur wisscn . Z')ol., BJ . 37, p. 4d,:

Proc.Lim South Wall > <•; ....... A . K . P., 1900, Mi-m. Ii . .t . Hist., vol. 5, p. 211. —

HARr.irr, C. \\'.. 190:. AnuTHMn N.irur.ili^l. \ "!. •;*'• !'• ^ N- M A^-'. 1904. Result, t' imp. s< i. I'nrn >• .i<- M.m.lt o, ' p. 5;; i >ir>'>. I .1 'in. i \i. lii i. l'.,l. |. I .!';•. -,. pp. 4^6. ^o,; MIC;. Si vplniMir.lu i-n .li-r Siboga Expcjitiun, Munog. 1 1, p. 28. — VASIH.I>>\, M|od. \'iiji-i h-'- I'l.LiiLrnn. \i. 11. p. ^i. Proc\anra+ M(doru + Slrnoptv<:ha+ Drsmontma (tn .-:r,i. \\ \n k'l.i., 1880, Syit. d'-r Mt-Jubtn, pp. 524-528.

The type species is C. ciifiillitn of the North Atlantic. Pacific, and Arctic Oceans. It is the largest of all known medusae.

GENKKIC CHARACTKRS.

Cyaneidae with 8 marginal sense-

oigans and with 8 adradial crescentic groups ot tentacles. Each group consists of several rows of tentacles. With radial muscle strands in the subumbrella.

When young only 8 simple tentacles arise in the adradial clefts between the ephyra lobes, bur later the margin grows beyond them, leaving them to project trom the floor of the subumbrella. In the mean- time the tentacles increase in number,

iinng a row in each adradius, but finally they come to lie in two or more rows, llaeckel has constituted a special genus tor each of these growth-stages. He calls the 8-tentaclcd stage "/YoryaM, -ii." The stage with 24 tentacles, 3 in each adradius, he names "Medora" and when then- are 5 tentacles in each row the medusa becomes a " Si, -ii'if't \, li,i" ; then as long as the medusa remains with the tentacles of each cluster in a single ro\v it is a " Des- mi,n,-tnn" and finally when older and the tentacles begin to develop in two or more K>\\s in each cluster the medusa is called a C.viini'it. It is possible that some medus;r nia\ become marine in, and never advance beyond, llacckil's " Desmonema stage,

onema chitrchiana. FIG. 378.— After Browne, in Trans. Royal. Soc. Edinburgh.

F.c. 379.- Young medusa, afta Vanhoffen in deutsch. Siidpolai l>ut jt js certain that others pass through this

Expedition.

condition and become mature as C.\<inf>i.

Medusae of C:\,in, ,i are abundant in the Arctic and Antarctic, but are not found in the tropics. Being dependent upon a fixed scyphostoma-stagc tor development, they are confined to the proximity of coasts where the water is relatively shallow.

596

MEDUS.'E OF THE WORLD.

The early development of the planula takes place among the folds of the copious mouth- curtains ol the adult medusa. Segmentation is total and regular but unequal, the cells of one pole being smallest. The gastrula results from simultaneous delamination and invagination at the small-cell pole. The blastopore closes. The planula attaches itself by its forward end and becomes a scyphostoma which acquires 15 to 20 tentacles and strobilates producing a number ot ephyrae. The details of this development are given under C. capillata.

It appears that the numerous so-called species of C \anea intergrade to such a degree that we can not maintain them, and I believe there are only two species: C. capillata of the north temperate and Arctic regions and C. aiuiaskala of the south temperate and Antarctic. In common with Pelagia, Chrysaora, Dactylometra, Aurelha and other world-wide forms of medusae, growth-stages, color varieties and local races have frequently been described as separate species, but as our knowledge increases many intergrading forms come to light thus reducing the so-called species to a few dominant types with numerous, closely related offshoots. It is unfortunate that the aim of the old systematic zoology was mainly toward the empha- sizing of distinctions rather than the indication of affinities and the discovery of relationships.

Cyanea is readily distinguished from Desmonema by its radiating muscle strands in the subumbrella, and its horse-shoe shaped clusters of tentacles.

Cyanea capillata Eschscholtz.

Plate 65, figs. 3 and 4.

Medina capillata, LINNE, 1746, Fauna Succica, Ed. i, p. 368, Nr. 1186; Systema Naturae, Ed. 10, 1758, tome i, p. 660; 1788,

tiimus i, pars 6, p. 3154. — FABRICIUS, 1780, Fauna Grocnlandica, p. 364.

C\anea capillata, Eschscholtz, 1829, Syst. der Acalephen, p. 68. — VAN BENEDEN, 1886, Fauna, littor, Belg., p. 77, taf. I, 2. — HAEOKEL, 1880, Syst. der Medusen, p. 529. — HAMANN, 1890, Internal. Monatsschrift Anat. Physiol., Bd. 7, p. 259, taf. 12. — BROWNE, 1905, Proc. Roy. Soc. Edinburgh, vol. 25, p. 771;. — MAAS, 1906, Fauna Arctica, Bd. 4, Lfg. 3, pp. 486, 511. — HOLT, 1902, Report Fisheries of Ireland, part 2.

Cyanea artica, PERON r.T LESUEUR, 1809, Ann. Mus. Hist. Nat. Paris, tome 14, p. 363. — MORCH, 1857, Beskriv. af Gro'nland, p. 95. — Ar.Assiz, L., 1862, Cont. Nat. Hist. TJ. S., vol. 4, pp. 87, 162; Ibid. 1860, vol. 3, plates 3-5^; plate 10, figs. 1-17, 19-21, 23-30, 33-35, 37, 38; plate ioa, figs. 1-40, 5-120, 14, 15, 17-40. — PACKARD, 1863, Canadian Naturalist and Gcol.,

vol. 8. — AGASSIZ, A., 1865, North Amer. Acal., p. 44, fig. 67. — HAECKEL, 1880. Syst. der Medusen, p. 530. — FEWKF.S, 1881, Bull. Mus. Comp. Zool. at Harvard College, vol. 8, No. 8, p. 166, plate 7, figs, i, 4, 5, 8-14. — WAGNER, 1885, VVirbcllosen des Weissen Meeres, Bd. I, p. 83, taf. 5, 6.--MAcMrRRicH, 1891, Amer. Naturalist, vol. 25, p. 287. — HARGITT, 1902, Science, ser. 2, vol. 15, p. 571. — MACALLUM. 1903, Journal of Physiology, Cambridge, Eng- land,vol. 29, pp. 213-241.— HYDE, 1894, Zeit. fiir wissen. Zool., Bd. 58, p. 531, taf. 34, fign. 54-62; taf. 35, fign. 63-79; taf. 36, fign. 94-96. — HARGITT, H)04, Bull. U. S. Bureau of Fisher- ies, vol. 24, p. 68. — MAAS, 1904, Result. Camp. Sci. Prince de Monaco, fasc. 28, p. 56. — VAN- HOFFEN, 1906, Nordisches Plankton, Nr. n,p. 53, fign. 16-19; C- capillata, p. 52, fig. 15; C. lamarcki, pp. 53, 64, fign. 35-37. — HARGITT, 1905, Journal Experimental Zoo]., vol. 2, p. 574 (variations). C\anea lumarckii, PERON ET LESUEUR, 1809, Ann.

Musec Hist. Nat., Paris, tome 14, p. 363. Cyanea postelsii, GOULD, A. A., 1841, (non Brandt) Report Invert. Massachusetts, p. 347. — STIMP- SON, 1853, Marine Invert. Grand Manan, p. 1 1 . Cyanea — — , M'KENDRICK, J. G., 1881, Journal Anat. and Physiol., vol. 15, p. 261 (coloring matter).

Cyanea lamarcki, DELAP, 1905, Annual Report Fis.h- FlG. 380. — Cyanea caftillata, after Vanhoffen, in Nordisches Plankton. cries of Ireland 1902-03, part 2, Appendix I

(reared from the egg in an aquarium). Cyanea lamarcki:, HAF.CKEL, 1880, Syst. der Medusen, p. 530 (literature). — JOIIBIN, 1906, Bull. Musee Oceanograph., Monaco,

No. 66, p. 27, fig. 28 (after Delap). — VANHOFFEN, 1908, Deutsche Sudpolar Expedition, Zool. 2, Bd. lo, p. 39. Cyanea lamarckii= C. capillata, M. INTOSH, 1885, Annals and Mag. Nat. Hist., ser. 5, vol. 15, p. 148. For literature of C. fnha and C. versicola see the detailed account of these varieties. Cyanea ferruginea, ESCHSCHOLTZ, 1829, Syst. der Acalephen, p. 70, taf. 5, fig. i.

C\anropsis behringiana, BRANDT, 1838, Mem. Acad. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 379, taf. II, fig. I. Cyanea ferruginea, HAECKEL, 1880, Syst. der Medusen, p. 1:31. — MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. 11, p. 28. — VANHOFFEN, 1906, Nordisches Plankton, Nr. n, p. 55, fig. zo.

PLATE 65.

Fig. I. CvaiH'" capilltita var. versicolor, mature medusa, natural size. In

the ocean off St. Catherines Sound, Georgia, December 29, 1904.

Two of the oral palps have been removed in order to reveal the

structures of the subumbrella. Fig. 2. Cyanea capillata var. versicolor, young ephyin.. 2.5 mm. in diameter.

Surface tow oft Cape Fear, North Carolina, December I, 1904. Fig. 2'. Sense-organ of the ephyra shown in figure I. Fig. 3. Cytnu'/i capillata, mature medusa, half natural size. Oral view of

quadrant of exumbrella, with mouth-parts and gonads removed.

Biological Laboratory, South Harpswell, Casco Bay, Maine,

August 28, 1908. Fig. 4. Cyanea capillata, young ephyra, 3.5 mm. in diameter, gt. internal

gastric cirri. Agassiz Laboratory, Newport, Rhode Island, June

29, 1893.

Drawn from life, by the author.

MAYER

PLATE 65

\

f J

\\/

at

'

si.\l \ I OBT< >\ll..i: CTANEA.

.V.I 7

( ? ?) Mtlunna formosa, HACCIOL, iS.Si, Report I),, -, ,-s, .., M,-.]u5x Challrngtr Eiped., Zool., vol. 4, p. I.

Cy,™« />«ic/i», BRANDT, 1838, Mem. A. .,,1 . s, , St. I1, vrsbourg, Sci. Nat., ser. 6, i..n,r 4, ,,. -,-,. taf. u, 13, I-,,- II »,.»,,.

1880, Syst. der Medusen, p. 532. YAMIOMIN-, 1006, Nordisches Plankton, Nr. 11, p. 55, fig. :, M,» . ,., ,

Arctica, Bd. 4. I,fg. 3, p. 506. Cyanra imporcata, NORMAN, 1865, Nat. Hist. Trans., Northumberland and Durham, vol. I

the British coast).

, p. II, I taf. (a young Cyanta from

Cyanea citrra, KISHINOI vi , 1910, Journal College of Sci. t'niversiu Tokyo, vol. 27, art. 9, p. |6, plate 4, figs. |6, 17 (this is C. jfTTuginta).

It is practically impossible to draw any fixed distinctions between the various hums of the great C\,m,-<i ot tin- North Atlantic. Intergrading forms are commonly met with and many ot the races are separated only geographically or upon color distinctions which are neither wholly characteristic nor stable. M,-Jusa ctipillata Limn", 174(1, is tin- oldi-st name applied to any ot these medusa;. The following are probably all \aintus ot One and the same species, C. capillata:

C.\anea capillala. Bell about 50010 1,200 mm. wide. Ocular and interocular clefts of bell-margin not sharp and narrow, but with evenly rounded curm. Bell, palps, and tentacles reddish or yellowish-brown. with ..r red gonads.

Vanhoffen, 1906, states th.it when the bell is 13 mm. wide there are 7 tentacle* in each adradial cluster, ih. one of each group being the longest. When 20 mm. wide there are 15 ter !t ,luster with -, I..ng ..nrs

in the middle. When 41 mm. wide there are 35; and when 86 mm. there art 63 tentacles. This variety is no! un- common in the English channel, North Sea, and coast of Norway in summer and autumn.

Var. lamarckii. Distinguished by the decided blue color of the bell and palps, the c..l,,r liring lighter at the margin than at the center of the bell. Gonads and tentacles nearly white. In other respects this form resembles C. capillala. Vanhoffen states that when the medusa is 43 mm. wide there arc only 20, and when 85 mm. wide only -, i tentacles in each group, thus being only about half as many as in the typical C. capillala of the same diameter. On the other hand the gonads in a medusa of C. lamarcki 43 mm. wide arc about as long as the palps, thus being larger than in (.'. mpillata. This form is found in the English channel along the coasts of France and Great Britain, at Helgoland, and in the entrances to the Baltic, but it does not extend into the Baltic. It becomes 300 mm. w ide.

Var. arctica. Supposed to be distinguished from the first two forms by the in i palar lappets which

do not project as far beyond the general contour of the bell-margin as in ('. . < iif>tlltii<i. It i \< r\ lart;e, tti.nit;!] : mens over 800 mm. in diameter are rarely met with. The bell is very variable in color but is ii..u.il|\ rii li brown and yellow, with deeply colored gonads and rich rosin-yellow muscles, and tent nl. , li i i..nnd oil the American north of Cape Cod, where it is abundant during the summer, becoming mature aii'i ill ,i|'|" .tiiiii- in < .ulv autumn.

FIG. 381. — Cyanea ferruginea, according to Eschscholtz, after Vanlu'lTen, in N'ordisches Plankton.

Var. fulva. A small yellowish-colored variety of C. arctica which ranges from Cape Cod southward to the Carolina coast. It is rarely over 200 mm. wide. At Newport, Rhode Island, it becomes mature early in June and is not seen in July, but on the coast of New Jersey it is found in August.

Var. nozakii. Similar to C. juh'a, but milk-white in color. Found in the Inland Sea of Japan.

Var. versicolor. A pink-colored southern variety of Cyanta fulva, which is even smaller, rarely more than lio mm. wide. It forms large swarms during the winter and spring off the coast of tin i ir.-s between Cape Hatteras,

North Carolina, and southern Florida.

Var. ferruginea. Of the North Pacific coasts of America and Asia. It is a variety of C. capillala and is apparently identical with the variety C." arctica." It becomes about 450 mm. wide and is light-yellow or orange with the stomach and radial pouches light-brown. The gonads are yellow and the tentacles reddish, although these colors are probably somewhat variable as in other forms of C\anta.

Var. poslchii appears to be only a local variety of C. capillata. It is found in tin- V-irh IVt.itu from the Aleutian Islands to Oregon and is distinguished by the 16 well-developed clefts which flank the rhopalar lappets and are about half as deep as the adradial clefts; moreover, according to Mertens. the contours of the lappcls .ire r\rnl\ rounded and even the clefts are not narrow, but widen inwardly with rounded contour. A modern study of this medusa is to be desired, for it is possible that Mertens over-emphasizes these peculiarities. The niedui..i is l.mnd between Sitka and the Aleutian Isl.m.l., Alaska.

The following is a detailed description of Cyanea" arctica" of the coast of North America :

Adult meJusa. — The disk is quite flat and lenticular and attains a diameter of 2,300 mm.

Medusae of this size are very rare, however, and the majority are not over 800 mm. wide. The

MEDUS.E OF THE WORLD.

umbrella margin is divided by 8 deep, adradial clefts into 8 principal lobes, which are about twice as broad as they are long. Each of these lobes is in turn divided by a median cleft, and there are also two slight notches upon the bell-margin on either side of the median cleft; the margin, therefore, displays 32 indentations, between which there are 32 lappets. The margin ot the bell is sharp-edged for the gelatinous substance, which is quite thick at the center of the disk, becomes very thin as one approaches the periphery. The 8 marginal sense- organs are found at the bottom ot the median niches of the 8 principal lobes of the disk. Each sense-organ is elongate and club-shaped, and protected above by a web which stretches between the adjacent lappets; proximal half of club quite thick, with a well-developed swelling upon its lower (subumbrella) side; this swelling is covered with wart-like elevations and provided with one or two papillae. Distal to this swollen region the club extends outward as a cylindrical tube which terminates in a swollen knob-like part containing an entodermal mass of crystalline concretions, but no ocelli. Two open pits project downward from the floor of the exumbrella on either side of the base of the sensory-club. The structure of the sense-organ in Cyauea has been studied by L. Agassiz, 1862; Eimer, 1878; and Fewkes, 1881. About 800 long ten- tacles arise from 8 adradial, crescentic regions on the floor of the subumbrella, about midway between the periphery and the center. The horns of these crescentic areas point outward and the tentacles are arranged in about 5 concentric rows in each crescent, the oldest and longest tentacles being on the innermost row. The tentacles are hollow and highly contractile; when fully expanded they attain a length of about 25 times the bell-diameter; their surfaces are thickly covered with nematocysts. Mouth 4-cornered and situated at center of subum- brella; it is provided with 4 long perradial mouth-arms, the margins of which are greatly folded, forming the curtain-like lips or oral fringes which hang downward in the water. Mouth-arms about as long as bell-diameter, and with their fringes appear as a complexly folded, contractile mass of curtain-like appendages hanging from the oral floor of the bell.

FIG. 382. — C\anea postelsi, according to Brandt, after VanhofTen, in Nordisches Plankton.

Gonads occupy 4 complexly-folded pouches which project from subumbrella floor at the 4 interradial sides of the stomach. Numerous clusters of small gastral cirri project from the bases of the gonads into the stomach-cavity; these are far more prominent in the young medusa than in the adult, for in the mature medusa they become hidden away at the bases of the pendant, pouch-like folds of the genital organs. There is a very powerful and con- spicuous system of circular muscles in the subumbrella; these muscles occupy a zone about one-eighth as broad as bell-radius and which lies adjacent to and centrifugal from the gonads. This zone of muscles is composed of 16 trapezia, the 8 in the rhopalar radii being only halt as wide as those in the adradii. 16 strands of radiating muscles extend from the outer side of the zone of circular muscles and pass outward on either side ot the sense-organs.

The central stomach is a wide, lenticular space in the center of the disk; peripherally it gives rise to 16 radiating pouches, the outer edges giving numerous branched canals which ramify through the lappets without anastomosing. The 8 pouches in the radii of the sense- organs are less than half as wide as the 8 in the radii of the tentacles. The tentacles and the stalks of the sense-organs are hollow and in direct connection with the gastrovascular space of

SEMAKOSTO.M !•:.]•; CT vNKA. 599

the medusa. There is no ring-canal. The gonads are great hollow bags forming part of the gastric system of the animal. There are deep clefts in the ahoral floor of the stomach giving it a reticulate appearance (see fig. 3, plate 65).

The gelatinous suhstance of the hell is translucent with a slightly hluish or yellowish tinge. The entoderm of the gastrovascular system is of a rich brownish-purple and the mouth-arms and oral curtains are chocolate-purple. The gonads and tentacles are either \ellnwish or reddish-brown, and the muscular system of the suhumbrella is brown or vellow.

This species extends from the southern coast of New Kngland northward to the Arctic Ocean. It thrives best in the colder waters, and specimens found south of Cape Cod are usually ot small size. It is worthy of notice, also, that south of Cape Cod the medusa- dis- appear about the middle ot [une, while in the cold waters of the coast of Maine the mature ones are most abundant in August and September. In Europe it is abundant off the coasts from Fiance to Northern Russia, and is found at Spitzbergen in August.

C.ynn, <i nitln n appears to be identical with the so-called C. jt-rriigin,-n of the North Pacific; and C. postelsil of the Pacific is a closely allied form.

The embryonic and larval stages have been studied by L. Agassiz, 1862; Fewkes, 1881; Hamann, 1890; MacMurrich, 1891; and Ida Hyde, 1894. Agassiz gives a series of figures illustrating the general developmental stages of the planula and scyphostoma, while Hyde gives a very complete account ot the histology ot the early stages. The eggs are orange-colored and provided with a membrane, and are dehisced from the ovaries into the gastric cavity, where they undergo segmentation among the folds of the mouth-arms and finally escape through the mouth ot the parent medusa as tree-swimming planula;. The segmentation is total but unequal, the cells at one pole being smaller than those at the opposite pole. A blastula is formed in which there is a large central blastoccel. The gasuula results from the rapid divisions ot one or two small cells at the small-cell pole, which form a layer that invaginates. Hyde finds no wandering inward of free cells, but McMurrich records this condition. The blastopore then closes over and the entoderm becomes entirely enveloped by the ectoderm. In this condition the larva becomes a pear-shaped, ciliated planula and swims actively through the water, the posterior, narrow end being that at which the gastrula mouth had developed. One sometimes observes netnatocysts in both ectoderm and entoderm at this narrow hinder end of the planula. The next stage in development is instituted by the formation of a shallow, crater-like, glandular imagination of the ectoderm at the broad, anterior pole of the pear-shaped planula, and then the animal sinks down and attaches itself to the bottom by this forward end. A cup-like depression of ectoderm then presses down upon the entodermal sac at the narrow posterior end and finally fuses with it, and eventually the mouth breaks through at this point.

The first pair of the radial pouches is formed from the entoderm, the second, in part at least, from the ectoderm ot the crater. MacMurrich, 1891, and Hargitt, 1902, observed that planulae in confinement encysted themselves during this stage, remaining thus for several days until the mouth is about to break through, when the embryos emerge from the cyst through a circular aperture at the center of its free, convex surface. Hyde, 1894, observed this, however, only in one embryo and it is possibly an abnormal condition due to unfavorable surroundings. Simultaneous with the formation of the mouth 4 tentacles make their appear- ance, and the scyphostoma finally acquires 15 to 20 tentacles. Hargitt, 1902, finds that lateral stolons are sometimes produced by the scyphostoma, and secondary scyphostomae bud out from these stolons. A number of ephyrae result from strohilizarion of the scyphostoma, and this may occur in 18 to 20 days atter the planula has attached itself but this period varies considerably.

The young ephyra 5.5 mm. in diameter (plate 65, fig. 4) has a simple 4-cornered mouth at the center of the subumbrella, and 4 smooth-edged, slightly raised lips. The 8 tentacular notches in the margin are much wider and deeper than the notches of the sense-organs. The tentacles arise from the bell-margin, but as the animal grows the margin extends beyond them and they thus come to project from the subumbrella floor ot the disk. 4 short, ento- dermal gastric cirri (ft plate 67, figs. 2, 3) are found upon the oral floor of the subumbrella near the interradial corners ot the mouth and pro]ect into the stomach-cavity. The gastric system in this stage consists ot a wide, lenticular, central stomach from which there extend outward ifi simple, radiating pouches in the radii of the tentacles and sense-organs. In

600

MEDUSAE OF THE WORLD.

later stages the young medusa develops an increasing number of tentacles and the lips form long curtain-like folds surrounding the 4-cornered mouth. When the young medusa is about 7 mm. in diameter there are a number of slender papillae upon the exumbrella and these are clustered especially at the aboral apex. In this stage the medusa rarely comes to the surface, but frequently spreads its oral fringes out over the bottom or sides of the aquarium and remains sedentary. The same habit is exhibited by the closely allied " Cyanea fnlva" which is represented in figs. I to 7, plate 66, and figs. I to 3, plate 67; and it is probably due to some such habit that the young are rarely to be found upon the surface while the large and mature medusae are very abundant. The scyphostoma and young medusa feed upon pro- tozoa, starfish, and mollusk larvae.

Macallum, 1903, studied the composition of the body-juices of Cyanea arctica and found them to be as follows:

	Na.	Ca.	K.	Mg.
		-. 84	t, 66
		•i 86	7 67

The SO3 is less in Cyanea than in sea-water by about 32 to 36 per cent and the medusa contains more iron and less iodine than does sea-water.

M'Kendrick, 1881, studied the chemical composition of the coloring matter of Cyanea and found that the blue pigment of Cyanea and Aurellia is in the form of granules surrounded by clear protoplasm. This pigment is soluble in acids, but is precipitated in neutral or acid solutions. Hence when the medusa becomes acid through decomposition after death the pig- ment dissolves out into the water, but during life it remains stable. This pigment matter of Cyanea shows two absorption bands in the spectrum, one in the red and one in the orange, very much as in Stentor cixruleits.

Holt, 1902, finds that in the North Sea this medusa is accompanied by young whiting.

Cyanea capillata var. fulva, L. Agassiz.

Plate 66, figs, i to 7; plate 67, figs, i to 3. Cyanea fulva, Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 119, 162. — Agassiz, A., 1865, North Amer. Acal., p. 46.

This southern variety is distinguished from the northern C. arctica by the light yellow or yellow-brown color of the entoderm of its gastrovascular system, which is never rich brown, as in the northern C. arctica. It is also much smaller, being rarely over 200 mm. in diameter. The lappet notches are more uniform than in C. arctica and the tentacles are much less numer- ous. The oral fringes, also, are less voluminous and by no means so complexly folded as in C. arctica. This variety appears in great numbers early in May on the southern coast of New England, and the medusae arrive at maturity about the middle of June, after which they suddenly disappear. We have, however, met with swarms of them about 20 miles off Barnegat Bay, New Jersey, early in August. This variety has not been taken north of Cape Cod. The development is similar to that of the closely allied C. arctica.

We may regard this as a local race of C. arctica, which ranges from Cape Cod, Massa- chusetts, southward to the Carolmas; where it is replaced by a still more southerly variety, C. arctica var. versicolor.

Cyanea capillata var. versicolor L. Agassiz.

Plate 65, figs. I and 2. Cyanea vcrsicolar, Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 119, 162. — Agassiz, A., 1865, North Amer. Acal., p. 46.

This form bears the same relation to Cyanea arctica var. fulva as fulva does to the northern C. arctica. It is smaller than fulva, but is distinguished especially by its pink coloration. Mature medusae are about 1 10 mm. in diameter and are found in swarms off the coast between Cape Hatteras, North Carolina, and Cape Canaveral, Florida. They are practically confined to pure open water and do not frequent the harbors. The mature medusae bear many ball-

PLATE 66. All figures are Cyanea cafillatu var. fitlva.

Fig. I. Planula 10 days old; enlarged view. Figure i'. Egg drawn to the

same relative size. Fig. 2. Scyphostoma with 8 tentacles, drawn in the act of feeding. I mm.

high.

Fig. 3. Scyphostoma with 14 tentacles, 24 days old. 1.5 mm. high. Fig. 4. Scyphostoma, oral view of a specimen with 10 tentacles. Fig. 5. Young medusa with bell 8 mm. wide; showing the exumbrella

papillae. There are 3 tentacles in each adradial cluster. Fig. 6. Young medusa with bell 10 mm. wide; showing the lips expanded

and spread out over the bottom oi the aquarium. There are 5

tentacles in each adradial cluster. Fig. 7. Marginal sense-organ of the medusa shown in figure 6.

Drawn from life, by the author, at the Agassiz Laboratory, Newport, Rhode Island, June 8 to July 9, 1895.

MAYER

PLATE 66

r

PLATE 67.

Fig. i. Cyanea caplllata var. fulva, young medusa 9 mm. in diameter. Showing its habit of resting with lips spread out over bottom of aquarium and its tentacles elevated, while at the same time the bell pulsates vigorously. Agassiz Laboratory, Newport, Rhode Island, June, 1895.

Fig. 2. Cyanea ca pillata var. fulva. Oral view of quadrant of bell of a young medusa 10 mm. in diameter, gt. internal gastric cirri. Agassiz Laboratory, Newport, Rhode Island, June 10, 1895.

Fig. 3. Cyanea capdlata var. fulva. Oral view of a medusa 15 mm. in diameter showing gastrovascular pouches (light blue) of subum- brella. Newport, Rhode Island, June, 1895.

Fig. 4. Aurellia aurita, young medusa 7 mm. in diameter, showing develop- ment of radial-canal system during formation of ring-canal. Tortugas, Florida, June 4, 1907.

Drawn from lite, by the author.

MAYER

PLATE 67

fft

|

*T

SKMAKMSTiiMK.K CH \\l \. lilll

like clusters of developing planula- gathered into the peripheral fanals of the gastric spafe. The gelatinous substance of the disk is translucent milkv-blue in color, while the "astro- vascular space. gonads, radial and circular muscles of the subumhrclla and the entodennal "I the tentacles aie purplish-pink. The outer parts of the veil-like folds of the palps are amber-brown. \\hile the pans adjacent to the mouth are pink. The concretions of the S sense-organs are reddish-brown. The planulx are yellow, hut the ephvra is pink.

The curtain-like oral fringes are relatively smaller than in C.\<in,n arctica. However, (he chief distinction of (.'. vi i >ii 'nl'ir is its peculiar pink coloration. Even in the young /-/>/i v " only 2.5 mm. in diameter, the stomach-cavity displays a deep purplish-pink, verv different troin i he pale yellow-colored ephyra ot the southern ('.. fulva.

Mature mcdus;e of (',. vet (it <il<ir occur in the winter months along our southern coast.

Amoni; thousands observed by the author dunn<; the winter ot 11)04 05 not more than a do/en lacked the pink coloranon and these resembled the variety ('. ciifiillntu var. jtil-rn. 1 hey were. ho\\e\ er, swimming among swarms ot the typical pink versn nlnr medusae. I he \ ai ict v verstcolor appears to he a well-marked local race ot (.'v.//;,.j capillata.

Cyanea capillata var. nozakii Kishinouye.

.• Flti .:,'•//, KiMUN'ii \i, lSi|i, III |.ip.mrsr, -, pp., I plate.

Kishinouye's paper upon this medusa is in Japanese, hut with a (Jerman abstract, and accompanied by two cleai h»uics ot the animal. The hell is flat and shield-shaped, 5 times as wide as high. if'O to 200 mm. wide. The hell-radius is 3 times as wide as the radius of the cential stomach. 10 rounded ephvra lappets, twice as wide as long. The ocular stomach- pouches are nearly rectangular. The tentacular stomach-pouches are twice as wide at their loses, and at the /one ot the sense-organs 2.5 times as wide as the ocular pouches. C'ohn, milk-white. Found in the Inland Sea ot japan.

This medusa is distinguished trom (',\<nit-<i capillata var. fulva only hv its color.

Cyanea annaskala von Lendenfeld.

8, p. 358-

Dcstnon, ", . ' . V AS si/. A., .in.l M A\ t K, t S<(S. Hull. Mus. Com p. Zool. at Harvard College, vol, ;:. p. K. pl.itr- 1 1 fig. i (young

inc. 1 1 ' .

..:.'fri,snllir=( I, VON I.IMIIM bin. iSSS, Bio]. iVntralhlatt. Bd. S. p. :iK.

•:stn<i tinnaietht (? young medusa), HAM KM . i^So. s\ .t. t|cr Mcjuscn, p. 52(1, t.if. ;o, tiyn. 1-4.

: • I, QUOY ET GAIUARD, 1824, Voyage de 1' C/r«znrVf Zool.f p. 570, plant i . ~.

Ki i i 101 •. i . MHO, Journal l'o!li-i;i- Sn. ToliMi, vol. 2?, art. i|. p. iS. i l.ni- j. iiK.. is. i.,.

Umhiella flat, shield-shaped, 70 to 2OO mm. wide and about 12 to 25 mm. thick, with .1 fe\\ protruding nett ling-wans at the middle ot the ex umbrella ; el sew here smooth. S marginal seiise-ni o.ins which lack ocelli, and with 32 marginal lappets divided into X main flaps ot 4 lappets each. These lappets are cxcnlv rounded and not wider at the end than at their bases; the if' ocular lappets aie about halt' as wide, as also are the 1 6 velar lappets adiacenr to them. There are S U-shaped clusters of long tentacles arising tiom the floor ot the subumbi ella. wi'h the concavin of each U directed outward. These tentacles are very numerous and aie arranged in } to 4 crowded rows in each U; thev are filiform and when extended are about $00 mm. loii";. The 4 complexlv folded, curtain-like lips are about as long as the bell-radius. The 4 pro:rusi\e gonads aie lai^e and complcxlv folded. The 8 ocular, radial pouches ot the central stomach are onh about half as wide as the S velar pouches. \11 ot the pouches break up into blindly-ending, branched, non-anastomosing vessels in the lappets. There is no ring-canal. The gelatinous substance of the disk and the tentacles are colorless. The entoderm of the gastral cavity is brown. Curtain-like lips intensely purple. (lemtal organs of the male are rose-colored; those of the female are orange-\ ellow . The medusa is distin- guished from the Cvancas of the northern hemisphere mainly In its brilliant coloration. It appears to be more closely related to (.'. versii "lor than to any other term, and it is interesting to observe that <.'. versicolot is the most southerly in its range ot any ot the northern (.'\aneas.

602

MEDUSAE OF THE WORLD.

This species is abundant along the temperate coasts of Australia and is found in Port Philip, Victoria, in large numbers from January to March. It is described in great detail by von Lendenfeld, who finds that the embryos remain attached to the mouth-arms until "they are nearly matured to young scyphostomae"; they then affix themselves to bodies in the water and produce a long stalk with a chitinous perisarc and 8 arms (tentacles ?). Accord- ing to von Lendenfeld the ephyra develops into an adult medusa by a complicated meta- morphosis. The lappets of the umbrella are said to be produced by fission, but this state- ment probably applies only to the ocular lappets, not to the 8 primary ephyra lobes.

In the variety purpura from Melbourne Harbor, Australia, the mouth-curtains are rich purple throughout, and in the variety margmata from Sydney their free-margins are purple, but elsewhere they are colorless.

FIG, 383. — Drymonena "victoria" after Haeckel, in Deep-sea Medusae of the Challenger Expedition.

Cyanea mullerianthe Haacke, from St. Vincent Gulf, South Australia, is a delicately pink-colored variety of this medusa, and Desmonema rosea Agassiz and Mayer is the same medusa when young and in the stage wherein the tentacles of each cluster arise in a single row.

Desmonema annasethe Haeckel, 1 880, may be a young contracted specimen of this medusa. The 16 so-called feathered, radiating ribs of the exumbrella present the appearance of being due to unnatural contraction. The tentacles arise in 8 U-shaped groups with 13 to 17 ten- tacles in each crescent. This form is described by Haeckel from a preserved specimen found off the west coast of South Africa. Color (?)

Dendy, 1889 (Proc. Royal Soc. Victoria, p. 1 12), describes parasitic actinian larvae found upon the mouth-curtains of the Cyanea of Port Phillip, Victoria.

S KM. \KOSTUMK.K — DEYMONEMA.

603

Genus DRYMONEMA Haeckel, 1880.

Drymonema, HAH KH . iSSo, Sit, uni^lior. Jena. Ges.-ll. fur Med. un.l Naturw., Jahrp. iSSo. Feb. zo; 1880, Sysl. der Mrdu«rn, p. 633; 1881, Report on I).,), i M.-dusx, Challenger Expedition, Zool., vol. 4, p. 124. Mi IIIR, F., 1883, Zool Anzeigcr, Jahrg. 6, p. 220.

The type species is Dr\>nr,n,-ni<i Jnlnintinn Haeckcl, 1880, of the Mediterranean. The same species was renamed D. "victor in" liy Haeckel in 1881. I), gorgo is a closely related form from the coast ot Brazil.

C;I-:NI-:RIC CHAR AC 1 1 KS.

Cyaneidae with 8 marginal sense-cumins. The tentacles an- nut grouped in separated clusters, hut arise diffusely in a wide annulus from the subumbrella. The central stomach gives rise to 16 radial pouches (8 ocular and 8 interocular) which branch dichotomously, hut do not anastomose. No ring-canal. Marginal lappets numerous. Development unknown.

I'll.. 384.— Drymonema "victoria," after Haeckel. in Deep-sea Mc.lus.e of the Challenger Expedition.

This genus is distinguished from ('.\<in,-n and l),\\ni',n,-n:,i hv the fact that its tentacles arise not in 8 separate clusters, hut from a wide annular /.one in the subumbrella. Moreover, the 16 dichotomously branched radial-canals, numerous velar lappets, and the radial furrows of the exumbrella are all distinctive of Drymonema.

Drymonema dalmatina Haeckel.

Drymonema dalmatina, HAH KM,, 1X80, S\ -I ..let Medusen, p. 641= /). -. icloria, 1 88 1, Report Deep-sea Medusa; Challenger Elpcd.,

Zool., vol. 4, p. 125, plates *,o, ;i. <!mi n I . lS'>>4. Arbeit. /.".'I. Inst. \\'ien. IM. ;. p. \)i. Drymonema cordelio, AN rn-\. |S<)2, Jena. Zcitsch. fur Naturwissrn, Bd. 27, p. 339, taf. 9, fign. 1-3.

Haeckel, 1880, had four small specimens of this medusa from the Dalmatian coast, Mediterranean. They ranged from 120 to 160 mm. in width and had only 64 radial furrows

(i()l MHDUS.E OF THK WORLD.

upon the exumbrella and 9 double lappets per octant, 144 in all. In Antipa's specimens from the Gull of Smyrna, Mediterranean, the radial furrows had increased to be 144 and thus corresponded in number with the lappets. Haeckel's specimens had only 80 terminal gastric- canals, while Antipa's specimens had 144.

The following is a description of Antipa's specimens, these being the more mature: Bell flatly rounded, shield-shaped, 500 to 1,000 mm. wide, 144 radial furrows on the exumbrella, and between them 144 marginal lappets. 8 marginal sense-organs in deep niches. 4 perradial, veil-like oral palps, each ending in 2 points, and thus (he palps have 8 adradial points. These palps are more than 1.5 times as long as the disk-radius and their outer edges are complexly folded. The numerous tentacles arise from the middle zone of the subumbrella, halfway between the center and margin line, and are 3 to 6 times as long as diameter ot the bell. There are 4 interradial protruding horseshoe-shaped gonads. Mouth-opening wide. Wall of mouth-tube thickened at 8 subradial places. The 1(1 stomach- pouches terminate in 144 dichotomous ramuli ( 128 tentacular and 16 ocular). Color reddish-white (pink ?). Gulf ot Smyrna, coast of Asia Minor, Mediterranean; Trieste, Adriatic Sea, GraefFe; Straits of Gibraltar ( ?) Haeckel.

Drymonema gorge F. Muller. Dr\rnonema Qorgo, MULLER, F., 1883, Zool. Anzeiger, Jahrg. 6, p. 220.

The disk is 20 to 500 (usually 300) mm. wide. "Mouth-arms" or palps longer than diameter of umbrella, whereas they are only about halt as long as this in D. dalmatina. The 8 ocular stomach-pouches fork once, thus giving 16 marginal diverticula as in D. dalmatina. The 8 velar stomach-pouches branch dichotomously 4 times, as in the mature D. dalmatina, but the fifth, sixth, eleventh, and twelfth branches in D. gorge* branch dichotomously a fifth time, and thus each of the 8 ocular stomach-pouches gives rise to 20 terminal branches in the lappets. There are thus 8X20+16=176 dichotomous terminal gastrovascular canals in D. gorgo and only 8X 16+16=144 in D. Jalmatina.

Found at St. Catharina Island, coast of Brazil. Rare.

This may prove to be a variety of /). J,ilmatina.

Genus (?) PATERA Lesson, 1843; DONACOSTOMA L. Agassiz, 1862.

Ptitcra, LFSSON, 184}, Hist. Zooph. Acalephe^, p. ;22. HAECKEL, 1880, Syst. der Medusen, p. ^;;.

( ?) Me/HJ/Hfl, HAECKEL, iSSo,loc.cit.. p. 534; 1881, Report Deep-sea Medus;c Challengri Expedition, Zool., vol. 4, p. i (abandoned

by Haeckel himself). (?) Donacostoma, Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. IlS, 163.

The type species of this problematic genus is Patera cerebnformis, first described as Dianaa cerebnformis by Lesson, 1829, Voyage de la Cof/iiill,-, Zooph., p. 124. planche to. The description and figure are evidently so inaccurate as to be all but worthless. Dianiza, Lamarck, 1816 (Hist. Anim. sans Vert., tome 2, p. 504), is a synonym of Cier \oniu.

GENERIC CHARACTERS.

Cyaneidae which are said to have 16 rhopalia. 16 clusters of tentacles arise from the subumbrella alternating in position with the sense-organs. Agassiz's Donacostoma has only 8 rhopalia, but 16 rows of tentacles.

Put era eereln-ij'irinis is said to come from near the Cape Verde Islands, tropical Atlantic; and another species Donacostoma icooJn L. Agassiz, 1862 (Cont. Nat. Hist. U. S., vol. 4, pp. 118, 163), is from the China Sea, and is said to have 8 "eyes," but with 16 branches ot tentacles like Patera, arranged in a single row in each lobe. Neither is well enough known to be worthy of description here, and indeed it is possible that both belong to the genus Dr\- moncma or even to Cyanca itself.

Family ULMARIDvE Haeckel, 1880, sens. ampl.

Flosculi.Lr+l'lmntiiLr, HAECKEL, 1880, Syst. der Medusen, pp. 5^, ;;<>• I'lmnii.l.r, VANHOFFEN, 1906, Nordisches Plankton, Nr. ll, p. 56.

FAMILY CHARACTERS.

Semaeostomeae with simple or branched radial-canals and a ring-canal. With hollow tentacles. 4 interradial gonads. 4 mouth-arms with folded, curtain-like margins.

81 \l V.EOSTOME I. I LOR] -< \. t''H."i

The medusae of this family arc cleisclv related to tin C'umeieLe, hut differ in that their radial-canals are placed in intercommunication In means of .1 marginal circular canal; moreover, th radial-canals anastomose in some ol the ".em-ia, and tins is iu-\ei the case in the Cyancidae.

The [H-nira ot the Ulmarul.e a ic .is lolhms:

I . Sl |;E AMI IV r\ll:kosl\ f .

The i'n> i I ihe margin in tin- ilcfts between the l.ipp.-i'. 4 evaginatedi sac-like gonads without subgenital

pits. S or ih marginal 4 unbran. mils.

( / • lun-« 11 (miniature r) = t'losculu Ft SAECCEL, i s^o. X rliop.ih.i, ^4 ' [I unbranchcd

ra.li.tl-i.in.il . Diiramaftiia, Cuua, 1877 I'lman : IKum. it i d and

intrrraji.il • I i branchedf tli B a

Parumbrosa, KISIUMC \i, nji". Similar to D

volume.) I' ndo<ti HAK K f i , i SSo. x Hi. i;..ili.i, eo tentacles, }8 lappets. K > ; lusn.

Dipllllniaris, MAAS, l<»ri> ' , , • : . \ hNHOrPENj l')^s. ' (l ' !'"(>. ill ' . ' il-can.il- ansr frnni

stomach. '! hr [6 rbopalar caoals branch and the i '» trnj.n ul.u nipK . All can.ils an- merged in a marginal

network of ana^> : n

:, Si I:H AMU v Si in N"\IN t .

Tentacles arise from floor of siibiimbrell.i . i I, sac-like e,on.i Is \\nhoi!- pits. 8 to |6 marginal S4?nsc-

orpans. 4 unbranche.l moutl]- Sllienfjniti, Ks. i: i i ! [ent.ule . P. rr.t.lial ainl interratlial

canals branched. Adradial can i'le an.i some br-in

Pharellofliora,Kv.f.\n\, iS;q. i d iiurnn.1 ins .iltein.itiii); with 16 iln 1.1 ..I tentacles. Radial-canals in the

rhop.ilar rajii arc bran. ; i !n simple-. 4 g,.n

Pornl:,.. \ • ii iiitN. njo;. \ninrr. .11 -traii^ht, unbramlie.l i.i.li,.!-. .in.il . NIIIH.I...I t^.m.uls in a ring around the ich-coargin.

; . Si ni \\iii. \ At R M r. i .

'rin- tentacles anil) • i '•.••' arise from thi ides of the disk above the margin i I ona v, uli rxi.Tn.il mi

pits. S marginal en . organs. 4 simple or bilnn .ir.-,l Tii.iiMh-.inir . \M: . I in : La]

.INK ///(.'. 1't RON AND Ki si v i i:, i So.). 4 : 1 1 1 1 . , i . . 1 1 1 1. 1 1 1 1 1 1 - ,i 1 1 1 1 . S. . 1 1 1 r or all of the radial-canal

anastomosing branches. ) gona i Aurosa, HAICKEL, i SXo. Similar to .lurrllia but with 4 bifurcated mouth-arms.

Subfamily UMBROSIN^. SUBFAMILY CHARACTKRS.

The tentacles arise sin»ly I'tom the hell-margin in clefts heiween lappets. 4 protrusive, haj;-like gonads without subgcnital pits. 4 unbranched mouth-arms.

(?) Genus FLORESCA Haeckel, 1880, sens. ampl. Floscula + Flortsca, HAFIKH. iSSo, Syit. .l.-r \1. ,lu en, p. 537, 538

Cl M UIl (II \K Ml IKS.

Haeckel's m-nera /•'/'»/ ///'' and /•'/'/;, M. .< may possil)l\- he the \ onii" stages of some niedus;c of the Ulmaridae. In these- loims \\( find that tin- central .stomach gives use to simple radial- canals which connect with one another Ky means nl a m.ii ^inal ring-canal. The tentacles arise from the clefts lie-i\\ee-n the- lappers, not from tlie floor ot the- subumbrella. \\ e must bear in mind, houevei, that in the your ol < ' the tentacles Hist appear in the clefts

hct\\ccn the lappets and late-r the- margin gn.us ontuaul, |..i\ing them to proje-cr from the stihumhrella. Indeed all tentacles in Sc\ phomeelus.e aie stiu.tuiis of the subumbrella.

Flosfiiln has 8 tentacles anil i'> maiginal lappets; Floresca has ^4 tentacles and $2 marginal lappets. Indeed Floresca pie-se-nts e-\ei\ .ippe-atance ol being immature and onlv an advanced stage of " /'l>»,-nl<i," both lieing one aiul the same species. Heith ceime from the tropical Indian and 1'acitic Oceans.

A brief descriplion of these meelnsa- mav In- e>f seivice should t!u-\ prove to be mature forms. Haeckel is the only naturalist \\lio has seen them.

"Floresca parthenia" Haeckel.

Floresca parthenia* /•'. fallaila, HAMKII, r I

Flosfula promcthrn (younger siare). llvi. n i . .' ". i 1- ' ''Tc

Bell rounded, 50 mm. wide, .jo high, \sitli a id-ra\ed pigmented star-like marking in the perrailii, intenaelii, and adradii of the exumbrella. S rheipalia, iS 4! ^ tongue-shaped

(iOli

MEDUSAE OF THE WORLD.

lappets. 24 (8X3) hollow tentacles 2 to 3 times as long as the bell-diameter. Throat-tube 1.5 times as long as the bell-radius and as the 4 complexly tolded, leaf-shaped lips. The central stomach gives rise to 16 unbranched radial-canals which are pined one to another by a marginal ring-canal. 4 interradial crescentic gonads with their convexities outward. These project from the floor of the subumbrella. There are no subgenital pits. The gonads are lined on their inner, concave sides by a row of gastric cirri. Color ( ?) Found at New Caledonia, New Guinea, and the Cocos Islands in the tropical Pacific and Indian Oceans.

Another specimen called "Floscula pandora" by Haeckel, 1 880 (p. 643), is from the tropical Pacific. The bell is 30 mm. wide, without a star-like marking upon the exumbrella, and with a short throat-tube hardly one-fourth as long as the long, narrow mouth-arms. Tentacles as long as the bell-radius. Lappets oval, sharp pointed, 1.5 times as long as broad.

These medusae appear to be immature, although Haeckel states that the gonads contained ripe eggs, but he studied only preserved specimens and cut no sections.

FIG. 385. — "Floscula promethfa."

FIG. 386. — "Floresca farlhenia.'

After Haeckel, in Das Syst. der Medusen.

Genus DISCOMEDUSA Claus, 1877.

Discomedusa, CLAUS, 1877, Denkschrift, Wien. Acad., Bd. 38, p. 42. Ulmaris+Umbrosa, HAECKEL, 1880, Syst. der Medusen, p. 545. Umbrosa, MAAS, 1908, Expedition Antarctique Fran^aise, Meduses, p. 9.

The type species is Discomedusa lobata Claus, 1877, of the Mediterranean. This may prove to be an arrested variety of Haeckel's UnJosa undulata of the west coast of tropical Africa. In UnJosa, however, there are 40 tentacles and 48 lappets, whereas in Discomedusa there are 24 tentacles and 32 lappets.

GENERIC CHARACTERS.

Ulmaridae with 24 (3X8) tentacles, 32 (4X8) lappets, and 8 sense-organs. The ten- tacles arise from the clefts between the marginal lappets. There are 8 simple, unbranched adradial canals, 8 branched, perradial and interradial canals, and a marginal ring-canal.

Haeckel's genus Ulmarts is apparently only the young of Discomedusa in a stage wherein there are only 8 tentacles and 16 lappets. His genus UnJosa bears the same relation to Disco- medusa that Dactylometra does to Chrysaora, the tentacles and lappets having increased from

S KM A K< IST( )M K.K — I)IS< '( )M K I) I S A .

fi()7

24 and 32 to 40 and 48, respectively. Thus DiscomeJusa is a growth-stage in the development of Undosa. The medusa of Trieste, Adriatic, appears to become mature, however, with only 24 tentacles, and it is interesting to observe that under unfavorable conditions in brackish water Dactylometra also becomes mature with 24 instead of 40 tentacles.

Discomedusa lobata Claus.

(?) Medusa stelligera EHRF.NBF.RC;, 1835, Abhandl. Acad. Berlin, p. 260. — 1836, Akalcphen des Rothen Meeres, p. 82. Discomedusa lobata, Cms, 1877, Denkschr. Wicn. Acad., Bd. 38, p. 42, taf. 8, 9.— GRAF.FFE, 1884, Arbeit. Zool. Inst. Wicn.,

Bd. 5, p. 343.

Umbrosa lobala, HAFCKF.L, 1880, Syst. dcr Meduscn, p. 546. Ulmaris prolol-ipui (? young medusa), HAF.CKF.I., 1880, lac. (it., p. 545, taf. 33, fign. 1-4.

Bell shield-shaped, flatter than a hemisphere, 150 mm. wide, 40 mm. high. The 16 ocular lappets are as wide as, but somewhat longer than, the 16 tentacular lappets. There are 24 tentacles, and 8 adradial ones are about as long as bell-diameter and twice as long and thick as the 16 secondary tentacles. The 4 mouth-arms are wide, tapering, somewhat longer than bell-radius and with curtain-like, folded margins provided with numerous ten- taculae. Mouth cruciform. Genital radius somewhat wider than half the bell-radius. The 4

crescentic gonads are convex outwardly and their ends nearly touch in the 4 per- radii. Centripetal to these gonads are 4 lines of long, numerous, gastric cirri, one row for each gonad.

The central stomach gives rise to 8 unbranched, adradial canals and to 8 per- radial and interradial vessels, each ot which gives rise to a pair of branched and anastomosing side-branches, the ter- minal ramifications of which fuse with the adradial canals and with the marginal ring-canal.

This medusa is found at Trieste, Adri- atic Sea, from December to March, the young being common in January and the adult in February and March. Claus gives the best description of it. It may be iden- tical with the imperfectly described. \l,\lu>< i stelligera Ehrenberg, from the harbor ot Alexandria, Egypt, in October. Ehren-

FIG. 387. — "U/maris protolypus," after Harckel, in Das Syst. der Medusen.

berg's medusa, however, appears to have about 40 short tentacles, all ot equal

length, and may therefore belong to Haeckel's genus UnJosa.

The young medusa of DiscomeJusa lobata passes through a stage wherein there are only

16 lappets and 8 adradial tentacles. The 8 adradial canals are simple and the 8 perradial

and interradial ones branched.

Discomedusa philippina, sp. nov.

This form is allied to D. lobata of the Mediterranean, but it appears to be smaller and to differ in the bluntness of its lappets, in having no fusions between the adradial and perradial and interradial canals, and above all by the blind branches on the outer side of the ring- canal.

Bell 29 mm. wide, flatter than a hemisphere, evenly rounded, exumbrella thickly be- sprinkled with prominent wart-like projections. Gelatinous substance fairly thick at center, thin at bell-margin. 8 rhopalia. 32 oval lappets all similar each to each, thus differing from D. lobata. 24 tentacles, the 8 adradial being longer and stouter than the 16 intermediate ten- tacles. The tentacles were all broken off in the specimens obtained by the Albatross so that their lengths could not be determined. 4 simple, crenulated lips at the end of a 4-cornered

(il)S

OF THK WORLD.

manubrium about as long as tbe bell-radius. 4 mterradial, crescentic gonads with their con- vexities outward and with a single row of simple unbranched gastric cirri along their inner sides. These gonads are about 5 times as wide as the perradial interspaces between them. Central stomach 15 mm. wide. 8 simple, unbranched, adradial canals arise from central stomach and proceed straight outward to ring-canal. Trident-like, pitch-fork-shaped, anas- tomosing canals arise from the 8 (perradial and interradial) sides of the stomach and break up into a network of vessels which fuse with the ring-canal. These networks, however, do not fuse with the 8 adradial canals, in this differing from D. lobata. On its outer side the ring-canal gives rise to 64 simple, unbranched, blindly-ending diverticula; a pair in each lappet. In formalin the gelatinous substance is transparent and the entodermal canal-system dull milky. The gonads appear to be mature, but the preservation is such that I can not be

FIG. 388. — Discomednsa philippina, sp. nov. Drawn by the author, from speci- mens obtained by the U. S. Fisheries Bureau steamer Albatross in Catingan Bay, Philippine Islands, April 20, 1908.

certain that this is the case. Six specimens were found by the U. S. Fisheries Bureau steamer Albatross, in Catingan Bay, Philippine Islands, on April 20, 1908. This medusa may possibly be the young ot Parumbrosa pol \labat a (see Appendix) but the large size oi its gonads and complexly branched canals renders this improbable.

Genus UNDOSA Haeckel, 1880.

Undosa, HAF.CKEI, 1880, Syst. der Medusen, p. 546. — MAAS, 1908, Expedition Antarctique Francaise, Mcduses. p. 9. Ulmaris (young medusa), loc. cil., p. 545.

The type species is UnJosa unJulata Haeckel, of the tropical Atlantic coast ot Africa. It is possible that Ehrenberg's Medusa stcllt^cra ot the Mediterranean may be identical with this species, but it is so imperfectly described that it is unrecognizable.

GENERIC CHARACTERS.

Ulmaridae with 8 sense-organs, 48 (8X6) marginal lappets, and 40 (5X8) tentacles which arise from the clefts between the lappets. 4 interradial protrusive gonads without subgi-nital ostia. 8 simple adradial canals, 8 branched perradial and interradial canals, and a ring-canal.

The genus is derived from DiscomeJusa through the multiplication ot lappets and ten- tacles. During the growth of the medusae they pass through a " DiscomeJusa" stage.

S|..M IEOSTOM1 -K i NDOSA, HI ri.l I.\I A i; I-.

I ill'. I

Undosa undulata Haeckel. .1 unJulaia, HAM KM, iSSo. Syst. .Ii-i ' ;.|i>. t.if. ;;. hrri. 5, 6.

Bell 120 nun. will i.1, 40 nun. high. Math rounded. A brown, in-raved, star-like titum mi exumbrella composed of pigmented nertlini: rid<;cs. 4X io-<8) sharp-pointed. o\al lappets, somewhat longer than wide anil projecting piomincntly: the \<i ocular lappets are somewhat longer than the others. ( >t the 40 tentacles, the S adradial are i to $ times as Ion;; as hell- radius, twice as long as the 10 secondary, and } limes as long as the 1(1 tertiary tent. u Us. All tentacles are hollow. The 4 mouth-arms rest-milk- those of .lun-lti,i tiuntii, hut their margins are more curtain-like and more tolded ,nul piouded with mum-ions trniacnlai tilaments. The 4 "utters of the mouth-arms are vnv deep. The 4 toltk-d. intei radial, bag- like gonads project from the floor of the snhumhrella. There are no siihgenital ostia. The genital tadius is ahout halt ihat of the hell itself. Maigin of central stomach circular. 8 simple, unhranchcil, adradial canals and X fpcnadial and intertadiall canals, which gui- rise to numerous side branches which in turn anastomose, loimmi: :l network of \essi-ls con- nectmt; all tfi canals one with another and with the marginal ring-canal.

The general color is bluish, and tin siai-like marking on the exum- hrella dark-brown. Found at l-d- nando I'o. coast ot (Jumea. Vtiif.i. I laeckel's " I 'hnnris f>rnt',t\'f>iii " horn St. Helena is probably the young of ibis species (/of. .it., iSSo. p. 545. taf. 33. fign. I 4).

Genus DIPLTJLMARIS MAAS, iqo8.

Diplulmarisj MAAS. 190*, n \ntarctiquc

Fran 'i.

I 'Imaropsit, VAMIHH IN, \>>c*. I ' 'p.J.n

Bzpedirion, Bd. 10, /.u<il. 2, p. 4^.

The type species is />: ftliilniuris untiir, tii ii, Maas. ii;oS, from the \ntaiciic < >cean.

'.! M-RIC CHARACTKRS.

-

.

;

. afu-r H.i' > ) • i ' der Medusen

Ulmaridae with i(> tentacles. 1*4 marginal lappets, and in marginal sense-ot'^ans. i'> luanched radial- canals m the radii ot the sense-organs and 10 simple straight radial-canals of the canals are joined by an anastomosing network ot \essels

I h ,. ;X(). I •;'.,',; iiiijiiliu

in the tentacular radii, near the bell-margin.

This medusa bears the same relation to ( nJ'i\,i that SanJeria does to Dactylometra. Indeed, there is a remarkable case ot parallelism of mutation in the I'elagnl.r and rimarul.i- as is shown in the accompanying table.

	I imi] !'• i	Famil) I Im.in.l.i .
^ lllop.lll.l, N Ti-[]t.H lr , I 1. Lip}'' !		riin.iriv (iitun 1 >

is a connecting link between the subfamilies I'nilnnn.lu, in w Inch the ten- tacles arise from clefts between the lappets, and SthenoniJit, in which they anse Itom tlu- subumbrella floor; for in the young Diplulmarii the tentacles arise from the subumbrella,

610

MEDUSA OF THE WORLD.

but later the bell-margin becomes cleft so that the tentacles project from the clefts. Diplul- mans resembles the genus Phacellophora in having 16 rhopalia.

VanhofFen, 1908, describes this medusa under the name Ulmaropsis drygahkii. Some of his specimens were more advanced than those seen by Maas, and they had 64 marginal lappets instead of only 32, as in those of Maas.

Diplulmaris Antarctica Maas.

Dip/ulmaris antarctica, MAAS, 1908, Exped. Antarctique Francaise, Meduses, p. 12, i taf.

Ulmaropsis drygahkii, VANHOFFEN, 1908, Deutsche Sudpolar Expedition, 1901-03, Bd. lo, Zool. 2, p. 45, fign. 10-12.

Ulmaropsis antartica, VANHOFFEN, 1909, Ibid., Bd. 10, Zoo]. 2, p. vi.

FIG. 390. — Diplulmaris antarctica, young medusa, after Maas, in Meduses Expedition Antarctique Francaise.

The largest specimen is described by VanhofFen, whose publication appeared only a few weeks after that of Maas. and is as follows:

Bell 42 mm. wide, 16 marginal sense-organs alternating with 16 simple, hollow tentacles. The sense-organs and tentacles are flanked by 64 slender, pointed lappets, the 32 lappets flanking the sense-organs being wider and longer than those flanking the tentacles. 32 radial- canals arise from the central stomach these being in the tentacular and ocular radii. The tentacular canals are simple and unbranched, but each of the ocular canals gives off 2 pairs

SEMAEOSTOME.E — DIPLUL.M AIMS, S'l H I : \( i\] A . 611

of side branches and thus 96 canals radiate outward toward the margin, before reaching which they are all connected by a network of anastomosing vessels. There are 4 lips and 4 gonads. 9 ephyrs and young medusae of this species were found by the German Antarctic Expedition between January and March. They ranged from 4 to 22 mm. in diameter. The species appears to be quite variable, for only 6 of them were i6-raved, while the 3 others were 12, 15, and 17 rayed respectively.

Two immature specimens were studied by Maas. The bell of larger was 35 to 40 mm. wide. 16 marginal sense-organs flanked by only 32 bluntly-pointed lappets. 16 hollow, tapering tentacles, somewhat shorter than the bell-radius. These tentacles arise from the inter-rhopalar clefts between the lappets. The rhopalar clefts are only halt as deep as the inter-rhopalar. Ventral stomach circular, nearly as wide as bell-radius. 16 trident-shaped radial-canals arise from the stomach-margin in the rhopalar radii and alternate with 16 straight, narrower, unforked canals in the tentacular radii. All the radial-canals give off anastomosing side branches in the outer parts of their lengths near the ring-canal. The ring- canal is at the zone of the origins of the tentacles, and 16 slightly branched radiating diverti- cula extend outward from it to the sense-organs. The 4 lips are bordered by curtain-like fringes. 4 interradial gonads with clusters of gastric cirri. Canal system yellowish-brown, the tentacles dull purple. The specimen was immature.

Maas also describes a smaller specimen only 15 mm. in diameter (fig. 390). This had 8 long tentacles alternating with 8 short. The short tentacles project from the floor of the subumbrella at some distance inward from the clefts between the lappets, and it appears that during growth the clefts extend inward until they meet the tentacles at the zone of the ring- canal. There are 16 simple, unbranched radial-canals in the radii of the tentacles and 16 trident-like canals in the rhopalar radii. None of these canals gives oft" side-branches close to the ring-canal, as in later life. 4 interradial oval gonads are now visible, and the short throat-tube expands into 4 pointed lips with folded margins. Central stomach circular, about as wide as bell-radius.

This medusa is found in the Antarctic Ocean from January to March where it lives along the edge of the Antarctic continent having been taken at Cape Adare, off Kaiser \Yilhelm II Land, and at other places.

Subfamily STHENONINJE. SUBFAMILY CHARACTERS.

The tentacles arise in linear clusters from the floor of the subumbrella. 8 to 16 marginal sense-organs. 4 protrusive, bag-like gonads without subgenital pits. 4 unbranched mouth- arms. Some single and some branched radial-canals.

Genus STHENONIA Eschscholtz, 1829.

Sthenonia, ESCHSCHOLTZ, 1829, Syst. dcr Acalephen, p. 59.— HATCKU, 1880, Syst. dcr Meduscn, p. 548.— VANHOFFFN, 1906, Nnrdisches Plankton, Nr. n, p. 56.

The type species and only known form is Sthenonia albida of Awatscha Bay, coast of Kamtschatka.

GENERIC CHARACTERS.

Ulmaridas with 8 rhopalia, 16 ocular lappets, 8 bifurcated velar lappets, and 8 adradial clusters of tentacles which arise from the subumbrella. 8 branched radial-canals in the rho- palar radii. Numerous simple or branched radial-canals in the radii of the velar lappets and a ring-canal. No subgenital pits.

Sthenonia albida Eschscholtz.

Sihtnonia albida, ESCHSCHOLTZ, 1829, Syst. der Acalephen, p. 59, taf. 4.— DE BLAINVIU.F., 1834, Man. d'Actinolope, p. 291, planche 36, fig. i.— HAECVEL, 1880, Syst. tier Malusen, p. 548.— VANH.I> > > N. 1C., i.joh, V.r.lisches Plankton, Nr. II, p. 56, fig. Z,

This form has not been seen since Eschscholtz described it.

Bell about 300 mm. wide, flat, and shield-shaped. 8 marginal sense-organs. 16 ocular and 8 velar lappets with evenly rounded, reentrant markings. Each ocular lappet has a small pointed projection into which the gastrovascular system extends, and each velar lappet has

612

MEDUS.E OF THE WORLD.

a pair of these projections. 8 adradial rows of tentacles arise from the suhumbrella in the intervals between the sense-organs; these rows being somewhat shorter than the intervals between them. The 4 mouth-arms are only one-third as long as bell-radius. The central stomach is less than one-fifth as wide as the bell, and there are 4 interradial clusters of gastric cirri. 8 radial-canals, each of which gives rise to several side branches, arise from the central stomach in the radii of the sense-organs. A simple and a forked canal arise in each of the 8 radii of the velar lappets. These radial-canals anastomose to some extent and fuse with a wide ring-canal in the zone of the sense-organs. On its outer side the ring-canal

FIG. 391. — Sthcnonia albida, according to Eschscholtz, after VanhofTen in Nordisches Plankton.

gives off a trident-shaped vessel in each rhopalar-radius and a pair of vessels in each velar lappet-radius. Bell whitish, gonads and canals milk-white.

Found by Eschscholtz in Awatscha Bay, coast of Kamtschatka, Siberia.

Genus PHACELLOPHORA Brandt, 1835.

Phacel/ophora, BRANDT, 1835, Mem. Acad. Imperiale des Sci. St. Petersbourg, ser 4, tome 2, p. 224; 1838, Mem. Acad. Imperiale des Sci. St. Peter sbourg, Sci. Nat., ser. 6, tome 4, p. 365. — HA ECKEL, 1880, Syst. der Medusen, p. 549. — VANHOFFEN, 1906, Nordisches Plankton, Nr. u, p. 58. — BROWNE, 1908, Trans. Royal Soc. Edinburgh, vol. 46, p. 247.

Heccfpdecomrna, BRANDT, Ibid., p. 380.

Cal/inema, VERRILL, 1869, American Journ.Sci., ser. 2, veil. 48, p. 117; Ann. and Mag. Nat. Hist., vol.4, p. 161. — FEWKF.S, 1888, Bull. Mus. Comp. Zool. at Harvard College, vol. 13, p. 235.

Pharellof>hora= HecctzJecomma, MAAS, 1906, Fauna Arctica, Bd. 4, Lfg. 3, pp. 506, 512^ Jena.

The type species is P. camtschatica, described by Brandt, 1838, from the North Pacific.

SEMAEOSTOMJ i. ni \< I u.oi'iKU; \.

613

(.1 Nl KIC CHAKAl I I US.

Ulmaridae with i'> marginal sense-organs ami mum-ions marginal lappets. I he ten- tacles arise in 16 simple, linear clusteis tnnn the Hum- ot the subumbrella, centripetal t<i the margin. Central mouth surrounded In 4 mouth-arms hearing curtain-like lips. Gonads are 4 complexly folded sacs which proji-ct oui\\ard in the 4 mtei radii from the floor ot the subumbrella. No subgenital pits. The central stomach gi\es rise to numerous radiating canals, some of which anastomose. There is a ring-canal at the bases ot the marginal lappets. Tentacles hollow.

of the Species nj Phacellophora.

Name.	P. camts-chatica.	I1. •., iila.*	P. ainbigua.-f-	P. ornata.f
Diameter of Jis-k in mm.	500 to 600	'55	1 50 10 200	55°
Shape and number of marginal 1-ipl" ' •	1 6 In lap- pet t> in rhop.il.n < 7 small lappets in each of 1 6 semicircular,	;2 narm-,v, rounded rhn| . 16 velar lobes.	(4X16) 64 lappets, all similar each lei i-ach, and evenly rounded.	4 ,(,) to (6 Xi6) lap- pets all >irnilar IM each and evenly rounded.
	\i-l.ir lobes.
sh.ipt- i if mouth-arms.	Loni;, narrow, resemb- ling <li" '• "t Vm-lia.	V iii 1'. ambigua.	Wide, curi.iin-like, and ri-srmblinis those of I jn.-a.	As in P. ambigua.
Number nf rajial-t jruiU	16 branched rh-«p.il.ii canals, and 5 X \ f> nn- ph- unbr.ini li-'.i r.i.li.il- • .in.il .	As in I'. aml>ii;"a.	id branched, rhopalar an,l ; to i; X|6 simple, mil't.iiu he 1 canals.	16 branched rhopalar and (1X16)10 (5X16] simple canals.
Number of tentacle in	20 tn 24	., to I 5	9	5 to 9
each cluster.
\Vhcrr found.	North I'.n iln , Niln-ri.i to l '.ilit'irnia.	M.'.lll, n.inr.ul. \ M. in.i, .im! otT tllr coa ' ot Japan .	I'.n iti. coa i ol \' >nli Aiin-rii .i, Washington,	North VI intii .northern coast of Maine. M.'lltWI.IlM. SoUtll rica.

intermediate in character betwei n /'. camtschatica and P. oniata. •(•Closely allied, probably identit.il.

Phacellophora camtschatica Brandt.

Phacellophora camticliatim. HKJ.M) i . i x ;S. M. ,,, . Vcad. Sci. St. P<tei bourg, tomi (,S( 6, p. ;dh, taf . 8.— ACASIIZ, A^

I SI,;. N'ortli Amer. Acal., p. 44. H *t rki i . iSSo. S\ st. ,!, r \l. lusen, p. ;4t|. VAMH.I i i \. P|O»,, Nordisches Plan: Xr. 11, p. 58, fig. 13.

Bell flat, 500 to 600 mm. wide. i»> marginal sense-organs each hi-m-ath a lar»e. projecting, coNcriii"; scale, which is flanked by 2 narrow, rhopalar lappets, each about halt as wide as the coverinn-scale itself. I'1 wide, nearl\ semicircular, \elar lappets, each cleft into - marginal lappets. 16 crescent-shaped linear clusters ot leniacles anse tiom siihumhrella floor ot velar lappets; the convexities of these crescents are inward and their horns outward, and each consists of 2O to 24 tentacles. Tentacles about as |on» as bell-i adms. The 4 mouth-arms .ire wide, tapering, and thick, and about 1.5 times as lono ;is lu-il-iadius; then b|is are folded in a curtain-like manner. Theie are 4 interradial, sac-! ike uonads with nan»u . pel radial inter- spaces between them. 'Uu uniral stomach gives list to I" iliopalar canals which send out lateral branches, and also to X'> (5 16) simple unbranched \elar canals. There is a ring-canal at the /one of the tentacles, on the outer inaigin of which theie anse 7 blindly ending, simple diserticula in each velar lappet and a trident-shaped branch in the radius of each sense-organ.

Bell colorless to bluish, gonads reddish-brown, canals vellow. tentacles light-violet.

This medusa ranges along the shores of the \<nth 1'acitic from Kamtschatka to San Francisco, California. It has not been figured since Meriens studied it.

Phacellophora sicula Haeckel. Phacillophora camt<chatic,i. H IK I\M',. < i. i \n R., 1878, Nerven ' t. mi .i Sinni organc Medu en, pp. 113, 114, taf. 9, fig. 15;

t.lf. 10, fig. l6.~H*M KM. iSSn. S-, 1. !,-| Mr,]u CD, p. s^l.

I'liMtllofiliara ambigua, KlsillNoevi , T')lo. |oiiinal College ol Si Fo\ ", \»\. 2~ . ait. <|. p. il, I IIL'.

The brothers llertwig describe the matginal sense-organs of this exceedingly ran medusa and give a very diagrammatic riguie of a part of the bell-margin. 1 he\ \\ere appar-

614

MEDUS/E OF THE WORLD.

ently under the impression that it was identical with P. ornata Brandt, from the Pacific, but Haeckel rightly distinguished it as a distinct species.

The following description is based upon my study of a single good specimen of this medusa collected by Dr. S. Lobianco at Naples, Italy, on January 1 1, 1901, and now preserved in formalin at the Naples Zoological Station.

Disk 155 mm. in diameter, flatter than a hemisphere, being only 55 mm. high. Exum- brella surface finely granular, being covered with small, thickly clustered nematocyst-warts. 1 6 marginal sense-organs, 4 perradial, 4 mterradial, and 8 adradial. Sense-organs set at bottom of deep, narrow clefts in bell-margin. The sense-club has no ocellus, merely a terminal mass of entodermal concretions. No sensory pit in exumbrella above the sense-club. 32 narrow, rhopalar lappets are separated by shallow clefts from the 16 wide, velar, simple lappets.

FIG. 391. — Phacellofhora sicula, drawn by the author, from a specimen found at Naples by Dr. S. Lobianco, January II, 1901. B, enlarged view of part of one of the tentacles.

The tentacles are arranged in 16 clusters and arise in a single row from the inwardly- arched outer margin of the ring-canal, on the subumbrella side of the 16 velar lappets. Each cluster consists of about 9 to 15 tentacles. In the Naples specimen these tentacles are about half (75 mm.) as long as diameter of disk and are set inward at a maximum distance of 17.5 mm. from the bell-margin. A narrow canal extends throughout the length of each tentacle on the inner (centripetal) side to its tip. A double row of mammiform, nematocyst-bearing papilla; extends along the inner side of each tentacle close to the tentacular canal, which sends off lateral diverticula into the papillae. The outer (centrifugal) side of each tentacle is pro- vided with circular muscle-fibers, which are interrupted along the line of the papillae.

SKMAKOSTOME.E — PH ACELLOPHORA.

615

The genital cross is about one-third (55 mm.) as wide as the bell itself. The 4 extruded, pouch-like gonads with their swollen, folded, wart-like genital-sacs resemble those of ('.\<int-<i. The 4 gonads are separated by very narrow intervals in the 4 pcrradii. The 4 wide, curtain- like lips also resemble those of Cyanea and are not quite as long as the radius of the bell. The central stomach gives rise to 16 rhopalar radial vessels which fork outwardly; and also to 48 (3X 16) inter-rhopalar radial-canals which are simple and do not fork. Lateral anasto- moses between these radial-canals are very rare. Ring-canal very well developed, about 3 mm. wide, while the radial-canals are each about 2.5 mm. wide, being about as wide as the spaces between them. The ring-canal gives rise to from 5 to 8 straight, simple, blindly-ending, centrifugal vessels in each velar lappet.

.:-•

FIG. 393. — Phaeellophora ambigua, according to Brandt, after Vanhitffrn, in Nordisches Plankton.

In formalin the exumbrella is yellowish-milky in color, the canal-system milky and translucent, the gonads dull orange to ocher, and the lips of a lighter hue of the same color.

Found at Naples and Messina, Mediterranean, and off the coast of Japan (Kishinouye).

This species is closely related to P. ambigua, but is distinguished by having only 16 wide, simple, velar lappets instead of 32 narrow ones, as in /'. mnbtgua. P. sicula is probably only an arrested variety of /'. ambigua in which the velar lobes remain entire and unclett.

Phacellophora ambigua Haeckel.

Haccxdecomma ambiguum, BRANDT, iS',8, Mem. Acad.Sci.St.Petcrsbourg, Sci. Nat.. MT. ft, tnmr 4, p. 380, taf.27, 18.— AGASSIZ,

A., 1865, North Amer. Acal., p. 4;. Phaccllophora ambigua, HAECKEL, 1880, Syst.der Mrdusrn. p. 550.— VANH. .KIN. 1 906, Nordisches Plankton, Mr. 1 1, p. 58, fig. 14.

Bell flatter than a hemisphere, 150 to 200 mm. wide. There are 64 (4X16) evenly rounded, marginal lappets all similar each to each. The sense-organs are sunken within deep, narrow clefts. Mouth-arms broad, curtain-like, similiar to those of Cyanca instead of being .7!<n-///a-like, as in P. cmiit^-h.itica. About 9 tentacles in each of the 16 linear clusters. The 16 rhopalar canals are forked and between them are 48 (3X16) simple, unbranched, radial

616

MEDUS.E OF THE WORLD.

vessels. The ring-canal gives rise centnpetally to a short diverticulum in the radius of each sense-organ and to 8X16 inter-rhopalar diverticula. The gonads are 4 interradial, sac-like, protruding pouches separated by narrow intervals in the perradii.

This species is closely related to P. sicula of the Mediterranean and Pacific, hut is dis- tinguished hy having 32 instead of 16 velar lappets. It is found along the Pacific coast of North America, Port Townsend and Straits of Fuca, Washington.

Phacellophora ornata Haeckel.

Callinema ornata, VK.RRILL, 1869, American Journ. Sci., ser. 2, vol. 48, p. 1 17; Ann. and M.ii;. Xat. Hist., vol. 4. p. if»i . — FEWKES,

1888, Bull. Mus. Comp. Zool. at Harvard College, vol. 13, No. 7, p. 255, plate 6. 4 fit;!,.; iSSS, Report U. S. Expedition to

Lady Franklin Bay, vol. 2, p. 40. Ptiacellophora ornata, HAECKEL, 1880, Syst. der Medusen, p. 643. — HARGITT, 1904, Bull. U. S. Bureau of Fisheries, vn] . 24. p. 68. —

VANHOFFFN, 1906, Nordisches Plankton, Nr. 1 1 , p. 59, fign. 25-26. — BROWNE, 1908, Trans. Royal Soc. Edinburgh, vol. 46,

p. 247, plate 2, figs. 3. 4.

Disk quite flat, with a slight dome-shaped aboral apex; it is about 350 mm. in diameter, and the marginal lappets droop vertically. The surface of the exumbrella is covered with

small nematocyst-warts. Gelati- nous substance of disk quite thick and rigid. 16 marginal sense- organs are set within niches be- tween the 32 ocular lappets. Ocular lappets about twice as long as velar ones, but not so numerous, there being 2 to 4 velar between each successive pair of ocular lap- pets. The clefts separating the ocular lappets are deeper and more distinct than those separat- ing i he velar lappets. Over 100 long tentacles arise from the floor of the subumbrella in a broken circle in 16 inter-rhopalar clusters at a short distance inward from the bases of the marginal lappets. The 5 to 9 tentacles between each successive pair of sense-organs varv considerably m size, the long- est being about equal to bell- diameter; they are hollow and flat, and there is a wavy double thick- ening along the centripetal narrow edge, which is covered with nema- tocysts. Mouth simple and 4- cornered, situated at center of subumbrella. The 4 mouth-arms are each about as long as bell- diameter, their free edges much folded. They are highly flexible and contractile. The gonads are found in 4 interradial, crumpled sacs which protect out- ward from the floor of the subumbrella at the sides of the mouth. Central stomach 4-lobed, being extended outward in the radii of the 4 genilal organs, very much as is the case in .-hit, -I I in. A large number of radiating canals run outward from the periphery of the central stomach to the circular canal, which lies at a considerable distance inward from bell-margin. The radiating canals in the radii of the sense-organs branch anil anastomose, while those in the tentacular radii are simple and slender. There are about 2 to 5 of these simple canals between each successive pair of anastomosing canals. Circular canal broad, somewhat sinuous, and it lies under the insertions of the ring of tentacles. Outwardly it gives rise to a blind canal

FIG. 394. — Phticfllophoia

SEMAEOSTOMK.E — PHACELLOPHORA, PORALIA.

617

in each velar lappet and a trident-shaped canal to each sense-organ and its adjacent lappets. Usually the outer ends of these blind canals are simple, but occasionally they bifurcate

<nK- .505)-

Disk transparent, the radiating and circular canals slightly brown in color. Sense-organs glistening white. Nematocyst-bearing edges of tentacles white. Central stomach oran«;e- yellow, the mouth-arms citron-yellow, the gpnads yellowish-brown.

1 his species is found at Eastport, Maine, and in the Bay of Fundy. It is very rare, and has been taken there only by Verrill and Fewkes. In 1908 Browne describes a closely allied or identical species from the South Atlantic about 200 miles east of Montevideo, South America.

I am gratefully indebted to Professor Verrill for permitting me to make drawings (figs. •j()4, 3<)5) ot the type specimen preserved in the Peabody Museum at Yale University

This species is closely related to P. ambigua, but is distinguished by its greater number of velar lappets and radial-canals. The velar lappets are also shorter than in P. ambigua.

Genus PORALIA Vanhoffen, 1902.

Poralia, VANHIIFFEN, 1902, Wissen. Ergcb. deutsch. Tiefscc Expedition, Dampier )'«/,//••/,/, Bil. 3, Lfj>. 1, p. 40.— BKIKI.OW, H. B., 1909, Mem. Museum Comp. Zool. at Harvard College, vol. 37, p. 4^, plate 13, figs. 1-5.

GENERIC CHARACTERS.

Ulmandae closely related to Phacellophora. \\ith numerous simple radial-canals, and a ring-canal, which on its outer side gives rise to blindly-ending vessels. The gonads form a ring

Fir.. ^<jv — Phacdhphorti ornnta. Portion of bell-rim.

of Outpocketings m the lateral wall of the stomach extending entirely around the base of the stomach, but interrupted at frequent intervals by vertical thickenings of the stomach wall. Tentacles ( ?) There are no subgenital pits in the floor of the subumbrella. The mouth parts are imperfectly preserved but appear to resemble those of ('\'<in,-n or Phacellophora.

This genus was founded by Vanhbffen, bur his single specimen was imperfect and imma- ture, and our knowledge of it is chiefly due to the studies of Bigclow upon the more peitcct specimens found by the Albatross in the eastern part of the tropical Pacific.

The type species is Poralia rufescens Vanhoffen, from the Indian Ocean and tropical Pacific.

Poralia rufescens Vanhbffen.

Poralia rufescrns, VANHOFFF.N, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Dampfer FalJivia, B.I. -,. I.fg. i , p. 41, taf. 4, fign. 15-16; ii)oS, Deutsche Sudpolar Expedition, Bd. 10, Zool. z, p. 47.— Bicr.Low, H. B., 1909. \l. MI. Museum Comp. Zool. at Harvard College, vol. 37, p. 45, plate 13.

In Bigelow's largest specimen the bell was 250 mm. in diameter. There were apparently 16 rhopalia, although some of these were destroyed so that the exact number was not deter- mined with certainty. The rhopalia resemble those of Phacfllop/wra and are set within deep

618

MEDUSAE OF THE WORLD.

niches. The sense-club is covered by a prominent scale, beneath which it stands in an almost vertical position. There is a deep exumbrella sensory-pit above each sense-club. There appear to be no distinct velar lappets, the bell-margins being only slightly wavy, excepting for the deep, rhopalar clefts. In Bigelow's large medusa 41 radial-canals arise from the periphery of the circular central stomach, but two of these anastomose so that only 40 extend to the ring- canal centripetal to the zone of the rhopalia. The ring-canal gives rise to a trident-shaped diverticulum in the radius of each sense-club and to one or two simple, blindly-ending divertic-. ula in the inter-rhopalar spaces. The canal-system, like the rhopalia, bears a striking resem- blance to Phacellophora. The mouth parts appear also to be similar to those of Phacellophora but are not well preserved in any specimen yet captured. The gonads form a nearly continuous ring around the periphery of the subumbrella floor of the stomach. This ring is not truly con-

FIG. 396. — Poralia rufescens, after H. B. Bigelow, in Mem. Mus. Comp. Zool. at Harvard College.

tinuous, however, but is interrupted by 1 8 or 19 thickened, vertical ridges in the stomach-wall. The gonads themselves thus consist of 18 or 19 outpocketmgs of the stomach-wall project- ing outward. The numerous, simple, gastric cirri are arranged in a single line arising from the stomach-wall on the inner side of the genital organs. The subumbrella is reddish-brown, the gonads being paler. The tentacles were lost in all of the specimens so that we know nothing of them.

Vanhoffen's specimen came from a depth of about 350 fathoms between Queen Emma Harbor and Siberut Island, Indian Ocean, and the two described by Bigelow were found by the Albatross in the eastern part of the tropical Pacific.

The radial-canals in this medusa appear toincrease in number with growth, for VanhofFen's specimen which was only about 60 mm. wide had 21 canals, while Bigelow's 250 mm. wide specimen had 41. VanhofFen's medusa had / or 8 (?) gonads, and both he and Bigelow believe that the young medusa is probably octoradial.

Subfamily AURELINJE L. Agassiz, 1862.

The numerous tentacles and lappets arise from the sides of the exumbrella above the margin. Gonads are invaginated sacs with external subgenital cavities. 4 simple or bifurcated mouth-arms.

Sl-.M LEOSTOME ]•: \i icu.l.l \. (il',1

Genus AURELLIA P£ron and Lesueur, 1809.

( ? ) Evagora, P£RON IT LESUF.VR, 1809, Ann. du Mus. Hist. Nat., P.ui-, tome 14, p. 343.

Aurcllia, IhitLj p. 357.

Ocyroc, Ihiit., p. 355.

Orythiat I.AMARCK, 1816, Hist. Anim. sans. Vert., tome 2, p. 502. Aurtlin, Ibid. f>. 512.

MeJusu, KM H-.C IHII.TZ, 1829, Syst. JIT Acalephen, p. 6|.

Monocraspedon-t- DiflocraifieJon, BRANDT, |S;X. Mr,,, AcaJ. Impi-riale dcs Sci. St. Pctcrsbourg, Sci. Nat., tit. 6, i.unc 4, pp. ro, 372.

ffiblis, LI:SSON, 184-,, Hi;t. Nat. Jcs Zoophytes, p. 339.

Clauslra, Ibiil., p. 578.

Aurelia, AI.A--M/, I,., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 1 !, 72, 78, 159. — AGASSIZ, A., 1865, N.utli Amrr. Ac al., p. 41. - CLAI'S, 1877, Denks. Aka I. Math. Nan. TV . r .. \\ i, -n.. BJ. 38, p. 19. — HAECKF.L, 1880, Syst. JIT Mi-.lu-.vn, pp. ^i , (144; 1881, Metagenesis unj Hypogcnc&is von Aurelia aurita, Jena. ;'i pp.. 2 taf.

Aurelia, v, IN I.»M»M > i n, |SS4. l'r..i . I. nine. in S,,e. NI-.V S.mtli Wales, vol. 9, p. Z79> — GoETTE, A., 1887, Ahhandl. zur Ent- wickelungBgcsch. Thiere, H, n 4. l.,:| ig (embryoli gj I, \,.\>M/ \M> MAVIR, 1899, Bull. Mui. Camp. Zool.al HarvarJ College, vol. 32, p. 171. — VAMIOI i IN, iXSS, Bibliothetj Zonl,ij;Ha. BJ. i. Heft 3, p. 23. — BATESON, iS-i,-. Mat, rial- fur the Stujy "f Variation, p. 428 (variations).— BROWNE, 1894, Quart. Journ. Micros. Sci., vol. 37, p. 245.— Hvot, 1894, Xeit. fur wi^sen. /t,,il., KJ. ^S, p. ^^. — \'A\ii'ih^N, 1888, Bibli"tli, t a /,,„ .lui;ica. Heft ^, p. H); lt^02. \\i ,11. I.r^eb. Jc-ntM'li. Tief^ec Expejition, Dampfer /',//,.'/; 1,1. H.I. : ! [, p. 41; 1906, Nordistliej Plankton, Nr. 1 1, p. 6o.--.MAAs, K)o6, l-'aiina Arcliia. BJ. 4, I.fg. 3, p. 507 (discussion of literature); 1903, ScyphomeJusen Jer Sibo^a K\pe iiti,,n. Monog

II, p. 2*i. I:KI MiMANN, It;O2 , i^eit . I U r ... i , 1 1 . /. '"1 ., H J . 7 I , p. 227 .- -HARGITT, '9Of, I'>urn. K \[>er. /ool., Vol. 2, p. 548.

Auricoma, HAI.I-KI.L, 1880, loc.cit., pp. 633, 644 (an abnormal Aurellia with 16 sense-organs).

G I- N I • R I C t 1 1 A R A C T K R S .

Ulmaridae \\nli a simple, central mouth-opening winch is surrounded by 4 well-developed, radially situated, unbranched mouth-arms m palps. X marginal M.-iiM-oi\i;ans. The tentacles an.- .small and alternate with an ec|ual number <>t shurr lappets. Both tentacles and lappets arise from the sides ot the exumhrella a short distance above bell-margin. The bell-margin is divided into 8 or 16 broad, velar lobes. The central stomach pves rise to a inimln i o| branched, radiating canals \\hich anastomose and are connected by a marginal rin^-canal. I here are 4 mterradial »onads and 4 well-developed, subgenital pits.

The name "Evagora" which takes precedence o\er "////<///-(" was applied to Forskal's i persea which is wholly unrecognizable, as is also '•(), yroe," and these names must therefore yield to "/I HI, Hi, i," which was first proposed by Feron and Lesueur for .Innlli.i iiiiriln ot Europe. They spell the generic name Aurellia.

The species ol this genus are among the most widely distributed ot Sc\ phomedus.e. beiiii.- found in all oceans and all latitudes. They are most abundant along the shores ot continents and large islands and are comparative!) iaie in the open ocean far from land. It is possible that the t'ossil .\!,Jn<in,i ,i,,tnt,i from the lo\\ei Cambrian ot Sue den is an AnrAlin.

Although tully a do/.en species ot .liin-lliii ha\e been described 1 believe that then aie but 3 reasonably well-defined tvpcs. Ot these ./. nnnt<i is ot world-wide distribution. .•/. \<i\>mt<i is found in i hi- Pacific, and a ihiid tairlv well-defined species is ./. inaLlr.-,-n\i\, described lu- ll. H. Higelow trom the atolls ot the Maldne Islands in the Indian Ocean. The distinctions

D

bet\\een main ot the "species" are not well ascertained, and there are mimeious \anelies cu local races. .7. ,innt,i is sub|ect to great individual \anation and some CP| these chance \aiia- tions have been described as species.

The species of .lunllni display much individual variability, and studies upon ibis subject have been carried out by Khrenbei" ' i^S1. Romanes I |S-'i --). Mrowiu ' 1X114 1^1. Duncker, So i1 by, 1 1 c id man, 1 in hank i I Si; 4 i. Hallow it/ i [898), and I I. HIM It I 1005 ). Ciooil review s ot t Ill- results of the earlier of these investigations are giv en In Bateson, 1895 (Materials for the Study of N'aiiations, p. 42''), and In \Lj.iss1y. and \\'oodworih, l8i/) (Hull. Mus. C'omp. Xool. at llarvaul College, vol. 50, No. 2). The abnormal individuals of . Inn-llin iinnt,i are peculiar in that they generalh presiive l he radial symmetry of the disk, even though the numbei of segments be changed. Radially symmetrical abnormalities appear to be about twice as numerous as are irregular ones. This law applies also to the variations of the Leptomcdusa Pseudoclytia [>,-nt<it« (see vol. II, p. i~Si.

Browne, 1894 and l8g5,discov ered that congenitall\' abnormal ephyr:i- of .-lunlliii survived fully as well as normal ones, and also that the abnormal eplnia- were no more abundant in 1892 than they were when F.hrenberg studied them at the same place in 1X^4. Kvidently the abnormal individuals do not acquire am fixed teiulency to perpetuate their own peculiarities

620

MEDUSAE OF THE WORLD.

rather than those of their normal parents, and thus the race as a whole maintains itself unchanged. About 22 per cent of the ephyrae and of adult Aurcllia have either more or less than 8 marginal sense-organs.

Most interesting physiological studies have been carried out upon Aurcllia by Romanes, 1885 (International Scientific Series, vol. 49, etc.), and also by Eimer, 1878. These studies show that the marginal sense-organs of Aurellia are locomotor centers which control the rhythmical pulsation. These marginal sense-organs tend to send out impulses to pulsation at various rates, but the fastest working sense-organ controls all the others and forces them to beat at its own rate. Parts of the subumbrella deprived of marginal sense-organs will still

Synopsis of the Races or Species of Aurellia.

	Aurellia aurita and its varieties.
	A. aurita Peron et	A. cruciata Haeckel.	A. colpota Brandt	A. flavidula Peron	A. hyalina Brandt.
	Lesueur.	(This is only a	= A. coerulea von	et Lcsueur (this is
		variety of A.aurita.)	Lendenfeld.	only a variety of A.
				aurita)=A. haban-
				ensis Mayer.
Shape of umbrella.	Flatly rounded to	Flatly rounded to	Flatly rounded to	Flatter than a hemi-	Flatter than a hemi-
	hemispherical.	hemispherical.	hemispherical.	sphere.	sphere.
Width in mm.	50 to 400	50 to 400	100 to 120	140 to 250	60 to 80
Height in mm.	20 to 125	20 to 125	40 to 50	50 to 90	20 to 30
Form of margin of	The 8 marginal	Sense-organs set in	Sense-organs set in	Sense-organs set in	Sense-organs set in
umbrella.	sense-organs set in	deep clefts.	shallow clefts.	clefts which may	wide, deep clefts.
	shallow clefts, 8			either be deep or
	simple entire, velar			shallow, being very
	lobes.			variable.
Number of velar	8 simple.	8 simple.	8 slightly notched in	8 simple.	8 simple.
lobes.			middle.
Form of mouth-	Small,lancet-shaped,	Small, lancet-shaped,	Large, complexly	Thick, lancet-	Similar to A. aurita.
arms.	with complexly	with complexly	folded, with lateral	shaped, with com-
	folded margins, but	folded margins, but	lappets. Very wide	plexly folded
	without lateral	without lateral	at their bases.	edges.
	lappets.	lappets.
Length of mouth-	r —	Only a little longer	r +	r+	r +
arms in terms of		than o.$r.
radius of um-
brella (r).
Length of genital-	One-third r.	Half r.	Half r.	One-third to half r.	One-third to one-
radius in terms of					fourth r.
radius of um-
brella.
Number of pri-	5 to 7, quite wide.	5 to 7	5	1	5
mary branches
arising from each
interradial geni-
tal sinus.
Character of ad-	Simple, unbranched.	Simple, unbranched.	Anastomosing with	Simple, unbranched.	All canals branched .
radial canals.			other canals, or
			simple and un-
			branched.
Color.	Very variable.	Very variable.	Light rose-red ten-	Variable as in A.	Variable. Trans-
	Milky to light-vio-	Milky to light-violet	tacles and gonads	aurita.	parent to reddish-
	let, rose-red, or	rose-red, or	deeper in color.
	almost colorless.	almost colorless.
Where found.	Atlantic coast of	Atlantic coast of	Indian Ocean to	Atlantic coast of	North Pacific.
	Europe and in	Spain and Medi-	Pacific.	North America,
	Mediterranean.	terranean.		Greenland to
	Vast swarms.			Florida and West
				Indies.
Remarks.	Development			Development as in
	through alterna-			A. aurita.
	tions by strobiliza-
	tion.

S i: M AKOSTOM KJE — AURKLLI A .

1121

respond momentarily by contractions to all sons of stimuli, electrical, chemical, thermal, or mechanical. Small parts of the disk with sense-organs attached pulsate somewhat more slowly than large ones. Romanes succeeded in maintaining the rhythmical movement ol the medusa in parts of the disk without marginal sense-organs by stimulating weakly with a con- stant or alternating current of electricity.

Romanes also found that a stimulus too weak to cause a response would if repeated eventually give rise to a contraction. This phenomenon is known as the summation of stimuli, and it is interesting to see that Lee and Morse, lyio (Proc. Soc. Experimental Biology and Medicine, New York, vol. 7, p. 38), find that this effect may be due to a rise in irritability, brought about by the action on the living substance of small quantities ot certain products of metabolism, especially carbon dioxide and lactic acid, the same substances which in gn .iti i concentration are important factors in fatigue.

Synopsis of the Races or Species of Aurellia — Continued.

	Aurellia auriu and its varieties.
	A. ilubia Vanhoffen.	A. viliana Agassi/, and	A. marginals 1.. V	\ . i 'Iila Urnv.-ne.
		Ma\er (immature).	(This is onh a \ arn 1\
			of A. flavidula.)
Shape of umbrella.	Flatter than a hemi-	limn- phrrical.	Flatter than a hemi-	Hemispherical.
	sphere.		Bphere.
Width in mm.	130	80	160 to 500	80
Height in mm.	43	40	60 to 1 20	4°
Form uf margin nf um-	As in A. fiavidula.	\ in A. flavidula.	As in A. flavidula.	As in A. aurita but
brella.				sense-cirg.in
				deep clefts and point
				upward toward exum-
				brclla,not toward bell-
				margin. Tin- S
				clubs arc thus di-
				rected 90° awav from
				direction assumed by
				A. aurita.
Number of velar lobes.	8 simple.	8 simple.	8 simple.	8 simple.
Form of mouth-arms.	Mouth-arms give rise to	Simple lancet-shaped.	As in A. flavidula.	Closely similar to those
	lateral lappets.			of A. aurita. The sub-
				genital ostia arc very
				small circular openings
				only 2 mm. wide.
Length of mouth-arms	Two-thirds r.	Half to two-thirds r.	r—	r +
in terms of radius of
umbrella (r)
Length of genital-radius	One-third r.	One-fourthto one-third r.	Half r+.	Four-fifths r.
in terms of radius of
umbrella.
Number of primary	7	5 to 7, all very slender.	7. As in A. flavidula.	As in A. aurita.
branches arising from
each interradial genital
sinus.
Character of adradial	All canals branched.	Simple, unbranched.	Simple, unbranched.	As in A. aurita.
canals.
Color.	p	Gonads, mouth-arms,	Gonads often light rosc-	Gonads salmon-colored,
		and tentacles lilac.	red, or blue, but colors	other parts translucent
		Other parts colorless.	variable as in A. tlavi-	whitish.
			dula.
Where found.	Persian Gulf.	Fiji and Tonga Islands,	Florida Keys, Krv We*	\l.ildi\i- Inlands, Indian
		South Pacific.	Havana to coast of	Ocean.
			Maine.
Remarks.	Described from a single	Swarms in harbors.	( ?) Development	Distinguished by its
	specimen.		slightly different from	peculiar sense-organs.
			that of A. flavidula
			(see Hyde 1894).

622

MEDUS.E OF THE WORLD.

Krukenberg, 1880, finds that Aurellia aurita contains 95.34 per cent of water and only 4.66 per cent of solid matter.

The planula larva commonly develops into a scyphostoma which gives rise to a number of ephyrae through strobilization. In aquaria, however, Haeckel, 1881, rinds that the planula may develop directly into a single medusa without passing through the scyphostoma-stage.j In this case the ocular lobes and tentacles grow outward around the gastrula mouth, and the gelatinous substance ot the planula becomes that of the medusa. In other cases the scypho- stoma develops into a single medusa which remains attached by a pedicel formed of the basal part of the scyphostoma, recalling the condition observed in the Stauromedusa?.

Herouard, 1907 (Comptes Rendus, Paris, tome 145, p. 601, Ibid., 1908, tome 147, p. 1336), finds a peculiar scyphostoma in an aquarium at Roscoff, which may possibly be that of Aurel- lia affected by adverse conditions of confinement, although he calls it T aeniolhydra roscof- ffiisis. It develops lateral buds, and in addition to these peculiar cysts on its pedal zone.

Synopsis of the Races or Species of Aurellia — Continued.

	Aurellia labiata and its varieties.
A.labiata Chamisso and Eysenhardt.*	A. "clausa" Lesson = young of A. labiata.*	A. limbata Brandt.	A.maldivensisBigelow,*
Shape of umbrella.	Hemispherical or flatter.	Hemispherical or flatter.	Hemispherical or flatter.	Flatter than a hemi-
				sphere.
\Vidth in mm.	200 to 300	So to 100	200 to 300	250
Height in mm.	ico to 200	40 to 50	ico to 150	90
Form of margin of um-	Margin with 16 deep	Margin with 16 clefts,	Margin with 16 deep	1 6 velar lobes with very
brella.	clefts, 8 ocular, 8 inter-	2 velar lobes in each	clefts, 2 velar lobes in	shallow Jntcrocular
	ocular, 2 velar lobes in	octant.	each octant.	clefts.
	each octant.
Number of velar lobes.	16, two in each octant.	1 6, two in each octant.	1 6, two in each octant.	1 6, two in each octant.
				Very shallow clefts be-
				tween lappets.
Form of mouth-arms.	Thick, pyramidal, short.	Small, thin, folded.	Triangular.	Lips large, wide, flexible,
	folded when mature,			curtain-like and folded
	but slender and simple,			with their free edges
	as in A. aurita when			lined by small tenta-
	young.			cles.
Length of mouth-arms	Two-thirds to three-	?	r —	r —
in terms of radius of	fourths T.
umbrella (r).
Length of genital-radius	One-fourth r.	?	Half r.	One-fourth to one-thirc
in terms of radius of				T .
umbrella (r)
Number of primary	As in A. aurita.	?	9	8 to ro branched and
branches arising from				anastomosing. Al-
each interradial genital				together about 48
sinus.				canals arise from cen-
				tral stomach.
Character of adradial	Usually simple, but may	?	All canals anastomose.	Simple, unbranched.
canals.	branch dendritically
	(without anastomos-
Color.	Light violet, gonads	Ovaries, canals, tenta-	Umbrella bluish, ten-	Variable. Bell delicate
	darker in color.	cles rose-red to wine-	tacles and margin	lilac. Canals and ten-
		red.	orange-brown. Velar	tacles violet-pink.
			lappets brownish-	Gonads violet or blue.
			black.
Where found.	Pacific coast of North	South Pacific coast, New	North Pacific coast of	Maldive Islands, Indian
	America to Malay	Ireland, Australia.	Siberia.	Ocean, in January.
	Archipelago.
Remarks.		Too imperfectly known	-	This form is chiefly
		for determination.		distinguished by its
		Probably identical with		curtain-like lips re-
		A. limbata or A.labiata.		calling those of Cyanea.

These are probably one and the same species and should be called Aurellia labiata

PLATE 68.

Fig. i. Aurelha aunta. Eastport, Maine, August 24, 1897. Natural size. Fig. 2. Aurelha aunta. Natural size of quadrant of bell. Tortugas, Florida,

May 4, 1905. Fig. 3. Aurellia aunta. Showing a marginal sense-organ seen from the

exumbrella side. Showing tentacles arising from exumbrella

side of bell-margin. Tortugas, Florida. Fig. 4. Anrcllia aunta. The bell-margin from the subumbrella side showing

the marginal lappets. Tortugas, Florida.

Drawn from life, by the author.

MAYER

.

PLATE 68

BEMAEOSTOMEJB— AURELIJ \.

These cysts or statoblasts are formed during resting pi-iiodx m about 15 davs and are incased in a chitinoUS en \elope. After one of these statohlasts is toinml ilu- so phostoma nioM-s a shoit distance and leaves it behind. The r Inn nous em elope ma\ then burst and tlu-cxst de\elops into a polyp with tentacles. When fed upon ova rj »l the sea-urchin this scyphostoma M miniated.

The early development ot'tlu- planula and scyphostonia lias been elaborately studied by Goette, Claus, Hyde, Smith, Friedmann, and others and the results of these researches will be reviewed under Aurellia auntti.

Friedmann, 1902, finds that in the SCyphostoma the tentacles develop in the order of 4, 8, 16, 24; and that the 12 and 20-tentacle conditions are intermediate phases.

Ann-Ilia aurita Lamarck. Plate 67, fig. 4; plate 68, figs. I to 4.

iMrJusa aurita, LINNE, 1746, Fauna suecica, No. 1287; 1747, Westgiita Resa, tab. 3, fig. 2; 1758, Syst. Nat., Ed. lo, tomus I p. 660.— GMELIN, 1788, Linne's Syst. Natur;e, tumus i, pars 6, p. 3153.

Medusa, sp., BORLASE, 1758, Nat. Hist, uf Cornwall, p. 257, plate 25, figs, ix ami x.

Aurelia auriia, LAMARCK, 1816, Hist. Anim. sans. Vert., tome 2, p. 513.— EHRENBERG, 1834, AbhanJI. Kgl. Akad. \Visscn., Berlin, p. 99 (variations). — DELI.E CHIAJE, 1841, Animali senza Vert., tome 7, Napoli, tav. 144, fig. i; t,u. 14^, tig. 2.— ROMANES, G. J., 1875, Nature, vol. 2, p. 29; 1876, Journal Linnean Soc. London, Zool., vol. 12, p. 528; vol. 13, p. 190, plates 15, 16 (variations); 1885, Jellyfish, Star-fish and Sea-urchins, etc., International Scientific Series, vol. 411 of pulsation).— HAECKEL, 1880, Syst. der Medusen, p. 552 (important list of literature).— MOBIUS, 1880, Zool. Anzeigcr, Jahrg. 3, p. 67 (medusa killed by freezing). — KRUKENBERC., 1880, Zool. Anzeiger, Jahrg.3, p. 306 (water content of bod) j. HA ECKEL, 188 1, Metagenesis und Hypogenesis von Aurelia auriia, Jena, 36 pp., 2 taf; Kosmos, Bd. 5, p. 29. — M'KENDRICK, 1881, Journ. Anat. and Physiol., vol. 15, p. 261 (coloring matter). — MOBIUS, 1882, Zool. Anzeiger, [ahrg 5, p. 586. (Aurellia from Kiel contains 97.92 per cent of water.)— CLAUS, 1883, Untersuch. ubcr Organization und Entwicklung Medusen, Prag. Leipzig, pp. 1-23, taf. i, fign. 1-20 (development).— GRAEFFE, 1884, Arbeit Zool. lust. \\ien. Bd. ;, p. 54;. GoTT«, 1885, Zool. Anzeiger, Jahrg. 8, p. 554 (development); 1887, AbhanJI. EntwickelungsgCBchichte der 'I Lure. H, it 4, I.eip/ic.. (development). — MARSHALL, 1888, (juart. Journal Microscop. Sci., vol. iS, |>. 84, I •uiprd imiM.le*). Sen KWIAKOI > , 1889, Morphol., Jahrb.,Bd. 15, H, i (structure of sense-chili)- MINCHIN, 1889, I'PK . Zoo]. So, . l.,,ndon, p. 583, 2 plates (brood- pouches of the oral arms). — CLAUS, 1890, Arbeit. Zool . In t . \\ien, Bd. 9, p. 85 (de\i-lopment ). tJom:, 1891, Claus und die Entwicklung der Scyphomedusen, I.eip/ig. 64 pp., 24 fign. (controvers) over the manner of development i S')2, Arbeit. Zuol. Inst. Vt'ien., B.I. 10, p. to (development of the scyphostoma).— DUNCKIR, 1895, Archiv. fiir N Jahrg. 60, p. 7, plate I (variations). -BROWNE, 1894, Nature, vol. 50, p. c;: ( I . .11 1 UH.MS). SORP.V, 1894, Nature, vol. 50, p. 476 (variations). — HERDMAN, 1894, Nature, vol. ^o, p. 426 (variations). -BROWNE, 1895, Quart. Journal Mur Vi., vol. 37, p. 245, plate 25, figs. 1-7; 1901, Journal of Biometrica, vol. i, p. 90, 3 diagrams (comparative variabilitv of rphyra and of adult medusa;). — HAACKE, 1897, Zool. Garten, Jahrg. 37, p. 357. UMIOWITZ, 1899, Archiv. Entwickelunr. - mech., Bd.S,p.239,taf. ^ (variations). — HEIN, 1900, Zeit. fiir wissen. Zool., Bd. 67, p. 401, 5 text-figs., laf. 24, ;^ (develop- ment).— GOTTE, 1900, Zool. Anzeiger, Bd. 23, p. 559 (development). FRIMIVMNN, 1902, Zeit. 1m . .1., Bd. 71, p. 227, taf. 12, 13 (development of tentacle, in scyphostoma). Ht IN, n^oi, /.(ml. An /either., Bd. 25, p. 637 (dcrelopm D VANHOKEF.N, 1902, \\'issen. Ergeb. deut^li. Tn t-ee r.\petl., Dampter l'ult!ii'i,i, HJ. }, Lfg. I, pp. 43, 44 (world-widi tribution of A. auriia); 1906, Nordisrhes I'lanklon, \r. I I, p. <>o, lign. z~ ;i . l)i I M', I'|O<>, 1 i-lienes Ireland, Su. Iniert., 1905, No. 7, p. 22, I plate (development ). (JonnM', 1909, Proc. Zool. Soc. London, part I, p. 78, plate 24. H^NMIIN, 1907, Naturgesch. des Tierreic!is., p. 332, fig. 4)').

Aurelia carulea, VON LENDENFELD, 1884, Proc. Linnean Not. New South Wales, vol. 9, p. 280.

Aurelia colpola, GOTTE, 1886, Sitzungsber. Akad. Wissen. Berlin, Jahrg. 1886, p. 836.

Aurelia aurita var. colpola, MAAS, 1903, ScyphomeduKO >ler Siboga Expedition, M.tnni;. i t, p. ;d, taf. t, fig. 9. — BROWNF, 1905, Fauna and Gcog. Maldive and Lacca,li\e An lup. -lagnes, vol. 2, p. 959.

Aurelia japonica, KISHINOUYE, 1891, Zool. Mag.ume, Tukv", vol. 3, No. 33, p. 289, plate 7.

Aurelia vitiana, AKASSIZ, A., AND MAYER, 1899, Bull. Museum Comp.Zonl. >1 Harrtrd ( liege, vol. 32, p. 171, plate 10, fig. 35; 1902, Memoirs, Ibid., vol. 26, p. 159.

Aurelia dubia, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, pp. 20, 24.

Aurelia ccerulea, VON LENDFNFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 180.

Aurelia cruciata, HAECKEL, 1880, loe.cit., p. 644.

Aurellia aurita from America. Plate 67, fig. 4; plate 68, figs. I to 4.

Medusa aurita, FABRICH/S, 1780, Fauna Groenlandica, p. 363, Nr. 356.

Aurellia favidula, PERON ET LESIFI R, 1809, Ann. du Mus. Hist. Nat. Paris, tome 14, p. 359, No. 91.

Aurelia favidula, LESSON, 1843, Hist. Zooph. Aial., p. 376. — AGASSIZ, L., 1860-'.:. i : i i 4, pp. 10, 12, ^i.

1 60; vol. 3, plates 6-9, i\a, I2&; plate 10, figs. 18, 22, 31, 32, 36; plate too, figs. 46, 13, 150, 16-41; plate nr, figs. 1-13 (development). — PACKARD, 1863, Canadian Nat. and (Icol., vol. 8.- V.* • i/. \ ., i ^'-;. V-nh \n:r r . V .tl.. p. 42. tigs. 65, 66. — HAECKEL, 1880, Syst. der Medusen, p. s-^. I i uns, iSSi.Bull. Mus. C'otnp. Ztml. at Harvard Coll' . 171,

plate 7, figs. 2-4, 6; 1884, Mem. Mus. Cump. /.mil. at Harvard College, vol. 10, No. 3, plate 8. — SMITH, 1891, Bull. M Comp.Zool.at Harvard College, vol.22, p. 1 1 ?. plates 1,2, figs. 1-12 (development). Hint, 1894, Zeit. fur wissrn. Zool., Bd. 58, p. 535, taf. 24, figs. 36-53 (development).- VLRRII i , 1873, Report I ,S ' 1 ish and Fisheries for 187 i

p. 723. — MACALLUM, 1903, Journal of Ph\ . i nul, vol. 29, pp. 213-241 (inorganic composition).

HARCITT, 1904, Bull. U. S. Bureau oi I-'i-herie- . \c.|. 24, p. (17 (>cypli»stom.i- vkitli stolons).— 1905, Journal Eiper. Zool., vol. 2, p. 148, figs, and plate (variations).

Medusa aurita, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 61.

Aurelia favidula, A. auriia, Ephwa octolobata, GOULD, 1841, Report Invert. Massachusetts, p. 348.

Aurelia sf.v-oz'rf/is, MtifccH, l8<;7, Beskriv. af Grbnland, p. 95.

Aurelia auriia, MORCH, 1857, Beskriv. af Gronland, p. 95. STIMPSON, 1853, Marine Invert. Grand Manan, p. n.

Aurelia habanensis, MAYER, 1900, Bull. Mus. Comp. Zool. at Harvard College, vol. 37, p. 69, plate 24, figs. 73, 74; plate 16, fig. 86 (Cuba to Tortugas).

624

MEDUSAE OF THE WORLD.

Dimensions in mm. of a mature specimen of Aurellia aurita from Naples, Italy, captured May 30, 1900. Bell-radius, 85; length of mouth-arms, 75; width of genital cross, 51. (See text-figure 397.)

The following is a description of the American form of Aurellia aurita, which has been commonly called "A. flavtJula":

Adult medusa. — Disk 140 to 250 mm. wide, 50 to 90 mm. high. When expanded it is flatter than a hemisphere, but when contracted it becomes hemispherical. Gelatinous sub- stance tough, thick at center, but thin at edge of disk. 8 marginal sense-organs at the bottom of shallow niches between the 8 broad velar lappets. Each sense-club is blunt and contains an ectodermal, proximal ocellus on the exumbrella side, a cup-like pigmented eye composed of both ectoderm and entoderm on the subumbrella side, and a distal entodermal mass of crystalline concretions. It is partially protected above by a bridge-like web stretching between the adjacent lappets. Lappets of considerable size on both sides of the club.

A single median pit projects downward from exumbrella surface just above the sense- club. Small and numerous tentacles arise from sides ot disk at a slight distance above margin and alternate with an equal number ot small, elongate, marginal lappets which similarly arise from the sides of the disk above the projecting margin. Tentacles hollow, with longitudinal strands of muscles down their subumbrella sides, and with broken rings of nematocyst-cells

on their exumhrella sides. Margin ot disk entire and simple except at places of the 8 sense-organs, where it is broken by notches. It forms a narrow, velum-like structure lying below the tentacles and marginal lap- pets. Central mouth-opening 4-sided, sur- rounded by 4 thick, stiff, gelatinous mouth- arms, the 8 free edges of which are much convoluted and provided with a row of numerous, small tentacles. These tree edges inclose a median trough or gutter, which extends down the middleof thelower side of each mouth-arm. These mouth- arms are each about as long as the radius of the disk; at their bases they are broad and their free margins are here greatly indented and folded in sinuous lines bor- dered by small tentacles. The 4 interradial gonads are horseshoe-shaped and alternate with the mouth-arms, and their position is marked on the floor of the subumbrella by 4 thick, horseshoe-shaped thickenings of the gelatinous substance, in the center of each of which there is a deeply sunken, subgenital pit. The radius of each of these horse- shoe-like regions is about one-third that of the disk itself.

Goodey, 1909, finds 4 interrradial, canal-like grooves in the subumbrella floor of the stomach leading from the gonads to the folds of the oral arms and serving to conduct the genital products away from the gonads.

The central stomach occupies a 4-lobed space, its outline being determined by the periph- eral edges of the 4 horseshoe-like genital cavities, and it gives rise to a complex system of radiating canals extending from edges of stomach to circular canal at bases of marginal ten- tacles. 8 separate, straight, non-anastomosing, adradial canals and 4 radial and 4 inter- radial, pitchfork-shaped systems of anastomosing canals; each of these systems consists of a single, straight, median canal and a pair of branching, lateral canals, which arise on either side of the median canal very near the periphery of the central stomach-cavity. The lateral canals each give rise to 3 to 5 radiating branches which anastomose sparingly and extend outward to the circular canal. These branches decrease in caliber and anastomose more frequently as they approach the circular canal. The gonads are found in 4 horseshoe-shaped

FIG. 397. — Aurellia aurita. Drawn by the author, from a specimen found at Naples, Italy, by Dr. S. Lobianco at the Naples Zoological Station, May 30, 1900.

BEMAEOSTOMEiG -AT IM. I.I.I v. 625

convoluted ridges on the subumbrella floor of the 4 genital cavities. '1'he bases of the genital ridges are beset with numerous, small, gastric cirri.

The gelatinous substance of the disk is ut" a translucent milky-white or yellowish-brown; spermaries usually slightly pink. In old individuals the gonads in both sexes art- white.

Common from Greenland to tin \Vist Indies. At Kastport, Maine, it is mature in Sep- tember, and at Tortugas, Florida, in May.

The American medusa is closely allied to AurAlia nuritii of Europe and is at most merely a variety of the latter. It may possibly ditfcr from its iMiiopean representative in the thickness and rigidity of the mouth-arms, which are very broad at their bases and often complexly convoluted at their free ed»es, but I have seen these same characters in Aurellia at Naples and consider the American and European medusa: to be identical.

A very complete description and numerous figures of the American medusa are given by L. Agassiz, 1860-62, Coin. Nat. Hist. U. S., vols. $ and 4.

Development. — The ova are dehisced from the gonads into the interradial grooves trom which they enter the median gutter of the mouth-arms and are In u- in.iined in small pouches near margins of free edges of mouth-arms and finally set tree in the planula stage. Minchin, 1889, gives a good description of these brood-pouches. Segmentation total and unequal, and a blast ula is formed which has a large, central blast ocu-l. According to Hyde, 1894, the gastrula may be formed in either one ot two different ways: ( l ) by the imagination ot a small part ot the blastula wall combined with the ingression of numerous cells from various pans oft be vv;ill of the blastula; (2) by inv agination of the wall of the blastula, aided only occasionally by the ingression of cells from the blastula wall. According to Smith, 1891, however, the gastrula is formed from a small invaginated region in the wall of the blastula, trom which there develops a single, continuous layer of cells, which layer finally completely tills the cleavage cavitv, thus giving rise to a 2-layered embryo with an open blastopore. Smith denies that this process is aided in the least by the ingression of cells from the wall of the blastula into the hlastocuel. Ik- finds, indeed, that a few cells are occasionally seen to wander into the blastula cavity, but these always degenerate without taking any share in the formation of the entoderm. lluse varia- tions in the mode of forming the gastrula have been seen in other Scyphomedusae, having been observed by Conklin in J.inuche, and Hyde and McMurrich in Cyanea. The blasiopou then closes and the entoderm becomes a closed sac entirely enveloped by the ectoderm. The larva then becomes ciliated and swims actively about as a pear-shaped planula. which soon attaches itself to the bottom by the wide anterior end. A crater-like depression (oesophagus) formed of ectodermal cells then appears at the narrow (now the upper) end of the animal, and this presses down upon the entodermal sac. The first pair of radial stomach-pouches is formed from the entodermal sac, while the second pair is formed, at least partially, from the ectoderm of the cup-like depression. The mouth breaks through and 4 tentacles appear. The larva then has 4 interradial, longitudinal, partial septa each formed ot a fold of the entoderm sup- ported by a central shelf of gelatinous substance. These septa extend from the margin ot the mouth to the lower end of the stomach-cavity. They form the 4 primary, gastric filaments of the future ephyra, and there are no septa in the central stomach ot the medusa.

As we have stated, it appears from the researches of Gone and ot Hyde that the two original pairs of stomach-pouches are derived alternately from the ectoderm of the (esophagus and from the entoderm of the primitive stomach, although Hyde shows that the lower aboral floor of the 2 oesophagus pouches is formed at least partially horn entoderm. Through division of the 4 original stomach-pouches we have finally 24 pouches, 10 entodermal and 14 mainly ectodermal, as follows: 6 diammetrically opposite peiiadial, 4 interradial. and the 4 connecting adradial pouches are ectodermal. 90° apait fiom these the 6 perradial and their 4 adjacent adradial pouches are entodermal. (See Gotte, 1887.)

One must remember that R. P. Higelow, 1900, finds that the 4 primary stomach-pouches ofCassiopfa x.unn, hana are wholly entodermal, and I !ad/i, 1907, finds that this is also the case in C/irvsaora. Moreover, according to I lad/i there is no ectodeimal imagination in Cliryxiora to form the mouth, but on tin contrary the throat is ^c.i^innl.J and lined with entoderm. The larva of .lin,-lli,i becomes a scyphostoma which finally attains a height of about 5 mm. and acquires 8, 16, and finally 24 long tentacles. The ephyr:i- aie developed tlinni<;h stiobili- zation of the scyphostoma. As many as 13 annular const unions may develop below the zone of

626

MEDUSAE OF THE WORLD.

oral tentacles, and then an additional set of tentacles usually develops below the last con- striction. As many as 12 disk-like ephyrae may be cast off one by one, and finally the scypho- stoma is left greatly reduced in size, but still provided with a corona ot tentacles. After all of the ephyrae have been cast off through this terminal budding the scyphostoma frequently develops irregular stolons from its sides and base. Haeckel's observations of other modes of development are discussed in the description of the genus Aurellia.

The young ephyra has 8 marginal sense-organs flanked by 16 lappets, the ocular clefts of which are only about half as wide and deep as the 8 alternating clefts. The throat is at first a simple 4-cornered tube and the lenticular central stomach gives rise to 16 simple, separate, radiating canals which extend outward in the radii of the tentacles and sense-organs. The tentacles then begin to develop (first one, then others laterally) in the 8 adradial spaces. The lips elongate at the 4 perradial corners and form the mouth-arms, and a peripheral ring-canal is formed by the radial-canals becoming T-shaped at their free, distal ends, and the sides of each adjacent T fusing. As the animal increases in size, blind canals travel centrip- etally inward from the ring-canal even before the ring-canal is complete, and fuse with the 8 perradial and interradial canals, which thus become pitchfork-shaped. (See fig. 4, plate 67.)

Full descriptions and very complete figures of the development of the various stages in Aurellia flavtJula are given by L. Agassiz, 1860-62. Hyde, 1894, gives a detailed and careful account of the development ot the planula and of the early stages of the scyphostoma, and Smith has investigated the process of formation of the gastrula. Clans and Gone, whose views are at variance, studied the development of the scyphostoma and its gastral pouches.

Macallum, 1903, finds that, in Aurellia flavidula living in brackish water, the salinity of the water may undergo considerable change during the day and yet the amount of NaCl within the body of the Aurellia remain practically constant. The medusa contains slightly less sodium and considerably more potassium than does normal sea-water. It contains also about the same amount of calcium as is found in sea-water, but less magnesium and 32 to 36 per cent less SO. He gives the composition of Aurellia, Cyanea and of sea-water as follows:

	Na.	Ca.	K.	Mg.
	IOO	1.84	•i.66	1 1. on
Contents of body-juice of Aurellia. . .	100	4-13 -i.86	5.18 7 6?	11.43

27 mature specimens of Aurellia from Tortugas, Florida, all collected at random from a single swarm on May 4, 1906, were of dimensions and proportions as follows:

Among 27 specimens —	Radius of umbrella.	Length of mouth-arms.	Radius of genital cross.
		8or
Proportions of specimen with largest gonads			0.51 T

Thus individuals among these 27 specimens displayed all of the characteristics of Aurellia aurita, "A. flavidula" "A. tnarginalis," and "A. habanensis" '; and all should be called A. aurita Lamarck, this name being the oldest. I wholly agree with Vanhoffen, 1902, that A. aurita is distributed over all warm and temperate oceans.

SKMAEOSTOMEjE — AURELLIA. 627

Aurellia aurita forma "marginalis."

Aurclia marginalis, ACASSIZ, L., 1861, Cont. Nat. Hist. U. S.( vol. 4, pp. 86, 160. — AcAssir.A., i865,North Amcr. Acal.,p. 43. — HAECKEL, 1880, Syst. der Mcduj.cn, p. 556. — HYDE, 1894, Zeit. fiir wiss.cn. Zool., Bd. 58, pp. 532, 544, taf. 32, 33, fign. 1-35.

This variety is larger than A. flaviJula, being often more than 300 mm. in diameter. Mouth-arms smaller than in A. flaviJula, being less than bell-radius in length. Genital pouches fully half as wide as bell-radius, instead of being about one-third this width as in ./. flaviJula. The gonads are of a pale rose color in both sexes.

Professor Hyde has made a careful study of the development up to the scyphostoma stage. The gastrula results from a peculiar process of delammation. Some of the cells <>t the one-layered blastula divide and their inner halves thus become free and wander into the blastula cavity where they eventually form the entodennal layer.

According to Hyde, however, the development of A . flaviJula is itself subject to much variation and the gastrula in this form also results in some cases from delamination. Hence the peculiar features of the development in A. marginalis are different only in degree from those observed by Hyde in A. flaviJula and are not of specific importance. Moreover, we must bear in mind that Smith finds that the gastrula of Aurellia flaviJula is formed by invagma- tion, and according to Gone and to Hein, 1900, the gastrula ot A. aurita is also formed by invagination. Staleness of the water in ordinary aquaria may profoundly alter the normal course of development.

I am convinced that "Aurellia inarginnlis" is only a variety of"//. flaviJula," which is itself specifically identical with A. aurita. For example, among 27 mature specimens of Aurellia found in a single swarm at Tortugas, Florida, on May 4, 1906, if we call r the radius of the umbrella, the length of the mouth-arms ranged from 0.89 to 1.04 r, the average being 0.95 r; also the radius of the genital cross ranged from 0.36 to 0.51 r, the average being 0.42 r. Agassiz called specimens of Aurellia with arms longer than r and the genital radii less than 0.5 r "A. flaviJula"; those having arms less than r and genital radii more than 0.5 r he would call "A. marginalis." It is evident, however, that the two forms intergrade, and this is true not only along the Florida reef, but also in the harbor of Eastport, Maine, where I found some individual Aurellias that conform to the proportions of "A. marginalis." It is safe to conclude that "A. marginalis" is merely a manuscript species and should disappear henceforth. L. Agassiz described it from the Florida reefs.

Aurellia aurita = "Aurellia dubia" Vanhbffen. Aurclia dubia, VANHOFFEN, 1888, Bibliutheca Zoologica, Bd. i, Heft. 3, pp. 20, 24.

The disk is 130 mm. wide and 43 mm. thick. The 8 marginal sense-organs are set in deep niches, as in A. flaviJula, and there are 8 broad, marginal lappets. The 8 mouth-arms are only two-thirds as long as the disk-radius. Genital-radius one-third ot disk-radius; 7 radiating canals extend outward from each genital sinus. All of the canals (ork; their branches are narrow and elongate in the middle and small and numerous at the margin. Color (?) Persian Gulf, March.

Described from a single specimen by Vanhoffen. Distinguished by its short mouth- arms and its having only 8 velar lobes instead of 16 as in A. lahiata.

Aurellia solida Browne.

Aurelia soliJa, BROWNE, 1905, Fauna and Geog. Maldivc and Laccadive Archipelagoes, vol. 2, plate 960, plate 94, figs. I, i; 1908, Trans. Royal Soc. Edinburgh, vol. 46, p. 149.

This medusa differs from Aurellia aurita in its marginal sense-organs, but in all other respects the characters of A. solida are well within the common ranges seen in A. aurita. In Aurellia solida each marginal sense-organ arises from the inner end of a deep groove which is open on the exumbrella side and bordered by the lateral lappets, but closed on the subumbrella side. In Aurellia aurita the sense-club points outward toward the umbrella margin. In Aurellia solida, however, the sense-club points upward toward the exumbrella and therefore at right angles to the position assumed by the sense-club in Aurellia aurita.

In Aurellia aurita there is a well-developed covering membrane or "hood" which extends over and above the sense-club on the exumbrella side, but in Aurellia solida the "hood" is a

628

MEDUSAE OF THE WORLD.

mere ridge or ledge-like mass of tissue covering the concavity in which lies the sense-club. The dorsal sensory-pit in Aurellia solida is a deep triangular funnel with a long, narrow mouth, and is quite unlike the shallow exumbrella sensory-pit of Aurellia aurita.

The bell is 80 mm. wide and 40 mm. high. Canal-system similar to that of Aurellia aurita, but the 4 circular, subgenital ostia are each only 2 mm. in diameter, whereas in A. aurita they are usually much larger. The oral arms are not quite as long as the radius of the umbrella. The genital radius is about 0.4 that of the umbrella.

Maldive Islands, Indian Ocean, and 15° west of Madeira in the North Atlantic.

Aurellia labiata Chamisso and Eysenhardt.

Aur,-lia labiata, CHAMISSO UND EYSENHARDT, 1820, Nova Acta phys. med. Leop. Car., tome 10, p. 358, planche 28, figs. I A, B . Aurellia labiata, DE BLAINVILLE, 1834, Manuel d'Actinologie, p. 294, planche 42, figs. I, 2. — FEWKES, 1889, American

Naturalist., vol. 23, p. ^92, fig. 2; Bull. Essex. Institute, Salem, vol. 21, No. 7, p. 122, plate 5, fig. 2. Diplocraspedon limbata, BRANDT, 1838, Mem. Acad. Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 372, taf. 10. Aurelia flausa (young medusa), LESSON, 1829, Voyage de la Coqitille, Zool., p. 119. Aurelia labiata + A. clausa+A. limbata, HAFCKEL, 1880, Syst. der Medusen, pp. 557, 558. Aurelia limbata, GOTTE, 1886, Sitzungsber. Akad. Wissen. Berlin, Jahrg. 1886, p. 836. — VANHOFFEN, 1906, Nordisches Plankton,

Nr. II, p. 61, fig. 32. — KISHINOUVE, 1910, Journal College of Sci. Tokyo, vol. 27, art. 9, p. 22.

B

FIG. 398. — Aurellia labiata. Drawn by the author, from specimens collected by the U. S. Bureau of Fisheries steamer Albatross at Masbate Anchorage, Philippine Islands, April 21, 1908.

A, oral view of medusa with one mouth-arm cut off. B, bell-margin seen from exumbrella side showing dorsalward migration of lappets and tentacles. C, section of bell-margin, the areas cut across being dotted, c, circular vessel; ex, exumbrella; /, marginal lappet; re, radial-canal; suf sub- umbrella; z>, velum-like bell-margin of bell; /, tentacle.

This species is distinguished by having 16 velar lobes separated by deep median clefts instead of 8 simple lobes as in A. aurita. The canal-system is similar to that of Aurellia aurita, but there is probably a greater tendency for fusions to occur between the adradial and other canals than in A . aurita. The bell-margin projects downward from the subumbrella side as

SI MA !•'.( iSTi iM K.E — AUUELLIA.

8 plain-edged, velum-like folds spanning between the sense-organs. The tentacles and mar- ginal lappets have migrated a considerable distance up the sides of the exumhrella, above the velar margin. A longitudinal strand of muscle-fibers extends down the subumbrella side of each tentacle and interrupts the rings of nematocysts which trend across its exumbrella side. When the medusa is old the mouth-arms become much thickened and folded as in Aurellia aitnta.

The dimensions of three specimens obtained by the U. S. Fisheries Bureau steamer Albatross at Masbate Anchorage, Philippine Islands, on April 21, 1908, are as folKms:

	Mm.	Mm.	Mm.
		l8q	128
Diameter across zone of gonads	57 74	53	4' £2

Aurcllin lnl'Kita is distinguished from A. aurita by having 1 6 notches in its bell-margin, by its peculiar velum-like, inter-rhopolar, subumbrella membranes representing the true hell- margin, and by the very small size of its subgenital ostia. The mouth-arms are also slmm-i than one commonly observes them to be in A. aurita.

Aurellia maldivensis H. B. Bigelow.

Aurelia maljii-ensis, BM.M u\\ , H. B., 1904, Bull. Mus. Comp. Zool. at Harvard College, vol. 39, p. 261, plates 6, 8, figs. Zi, :;.:-.

Bell 250 mm. wide and about one-third as high. 8 marginal sense-organs, flanked by small, pointed, ocular lappets. 8 wide interocular or velar lobes are each divided into 2 by

Fin. ',()'!• -.lurrlliii iiiulJirensit, after H. B. Bigelow, in Bull. Mus. Comp. SCool. at Harvard Collcgi-.

a very slight, central depression, thus forming 16 lobes as in ./. lulmitii. About 500 small tentacles alternate with an equal number of small, dorsal lappets as in .4ur<-llia aitnta. The 4 mouth-arms, or palps, are large and curtain-like, recalling those ot C.yanca; their lips are complexly folded and bear numerous, short tentacles. About 48 radial-canals arise from the central stomach, the 8 canals to the marginal sense-organs and the 8 adradial ones do not branch, but all of the others branch, and occasionally anastomose, so that about i," canals reach the circular vessel at the margin. The 8 canals to the sense-organs each give off 2 side-branches in the immediate neighborhood of the sense-organ. These side branches extend to the circular vessel. The 4 gonads are small and horseshoe-shaped and have wide subgenital pits.

The bell is of a delicate lilac, the canals and tentacles pinkish-violet, and the mature gonads bright violet. The color is, however, variable, some specimens being blue.

Abundant in the lagoons of the atolls of the Maldives, Indian Ocean, in January.

(WO

MEDUSA OF THE WORLD.

The comparative dimensions and other details are stated in the table giving a synopsis of the species of Aurellia.

In its cleft, velar lobes it recalls A. labiata, while in its wide, curtain-like mouth-arms it stands alone among Aurellias. Indeed its peculiar mouth-curtains are all that separate it from ./. liilnata.

Genus AUROSA Haeckel, 1880.

Aurosa, HAECKEL, 1880, Syst. tier Medusen, p. 559.

The type species and only known form is Aurosa furcata Haeckel, from the tropical Indian Ocean.

GENERIC CHARACTERS.

The medusa is similar to Aurellia but the 4 mouth-arms are bifurcated at their outer ends. There are 24 anastomosing radial-canals and a marginal ring-canal. 4 mterradial gonads, 8 rhopalia, 8 velar lobes, and numerous small tentacles as in Aurellia.

Aurosa furcata Haeckel.

Aurosa jurcala, HAECKEL, 1880, Syst. der Medusen, p. 559, taf. 33, fign. 7, 8.

Bell flat, shield-shaped, 80 mm. wide, 30 mm. high, 8 velar lappets as in Aurellia aunta. 8 marginal sense-organs. Tentacles small, numerous, arising from exumbrella side of margin

FIG. 400. — Aurosa jurcala, after Haeckel, in Das Syst. der Medusen.

as in A. aunta. Gonads as in A. aurita. Genital radius half the bell-radius. Central stomach gives rise to 24 radial-canals, all of which give forth anastomosing side-branches. There are 4 perradial, 4 interradial, and 16 adradial canals. Thus each genital pouch gives rise to 5 radial-canals, and the perradial canals arise from the angles between the genital pouches. The peripheral network of anastomosing canals becomes narrower in its mesh the nearer the vessels are to the marginal ring-canal. The 4 mouth-arms resemble those of Aurellia aurita, but each one bifurcates near its outer end. Their curtain-like margins are much folded.

Found near Cocos Islands, Indian Ocean, southwest of Sumatra.

HHI/OSTIIM.B. I'l.l]

Order RHIZOST01VLE Cuvier, 1799.

Rhizostom*, CivltR, 1799, Journal de Phys., tome 49, p. j\(>. HAM KM, iSXo, Syr. ,|.-r Mr In . -n, p. 560.- HAMANX, iSSl,

Jena. Zcit. fur Naturwissen., Bd. 15, p. 24;. CIAI ^, iSS^, t'ntersuch. uber Organisation und Ent»icl.. ,1, i \I.

Leipzig, p. 5o; 1886, Arbeit. Zool. Inst. Wien, Bd. 7, p. no. VON LCNDF.NFF.LD, 1888, Zett. fur wissen. /....I., li.t. 4-.

p. 208.

Rhixostomea, A<.A-<SI/ , I... iS'>2, p. 208, c'onr. N'.it. Hi*t. I", s.. vol. 4, p. i4<}. Rhizosiomata, VANHOFFLN, 1888, Bibliotheca Zoologica, Bd. i. Heft. 3, p. 39.— MAAS, 190-,, Scyphomedusen der SiboRa Eipcd.,

M<iiiog. n, p. 88; 1906, Revue Suis,r ,!, /,<„,!., tome 14, p. 100; 1907, Ergeb.und Kortsclirittc der Zoologic, BJ. I, p. 201. Rhizostomidx, ESCHSCHOLTZ, 1829, Syst. der Acali-ptn-n, p. 42.

CHARACTERS OF THE ORDER.

Scyphomedusae without marginal tentacles*, ami \\iili numerous mouths which are borne upon 8 adradial, fleshy, branched arm-like appendages which arise from the center of the subumhrella. The lips ot the numerous mouths are bordered by minute, constantly moving tentacles.

The rhopalia and marginal lappets of the Rhi/ostomae are similar to those of Semajos- tomeae. The Rhizostomae are the most highly differentiated Scyphomedusae, and owing to the generally tough consistency of their gelatinous substance and their large size thev have often been found preserved as fossils, especially in the lithographic slates of Solenhofen and Eischstadt. They are tropical forms and none are known from the polar regions. The genus Rlnzostotna is the only one which extends far into temperate regions, and the majority of the genera are confined to the warm waters of the Indo-Pacific region. A few are found in the tropical Atlantic and the Mediterranean. The Rhizostonuc develop, in so far as \\i know, through strobilization from scyphostomae. Phylogenetically they are derived from the more simply organized Semaeostomeae, but they have lost their marginal tentacles, though in Loboiit-mathe marginal lappets have become greatly elongated and may in some respects function as tentacles. Theephyra of the Rhizostomae has a simple cruciform, central mouth, as in the Semaeostomeae, but the 4 rays ot the cross soon fork at tlu-ii outer ends and then grow i>m\\.inl in the form of 8 adradial, fleshy, mouth-bearing appendages, which branch in a charaeteiistic manner and constitute the so-called "mouth-arms." The primitive central mouth may then be obliterated by the coalescence of its lips, but numerous other mouth-openings remain in the gutter-like grooves which extend down the ventral sides of the mouth-arms; and these mouths may also extend over parts of the dorsal sides of the mouth-amis. The sem;costomous genus Aufosa with its 4 bifurcated mouth-arms, which in other respects resemble those ot '.inr, l/m, appears to be a connecting link between the Semasostomeas and the Rhizostomx.

The gonads of the Rhizostomae are invaginated as are those of Aurellia, not protrusive as in Cyanea. In the young medusa; of all Rhizostonue and in the mature medusae of some

naaaa* genera such as (.'<;< M<if>i-ii there are4sepa- \ rate genital sacs which project into the

Is — -J central stomach-cavity ot the medusa. In many Rhizostomas such as in Cotylorhiza, .\f,i\tifli<i.<, etc., the inner ends of the 4 primitive, genital bags may coalesce and their walls break down, forming a cruci- form cavity beneath the stomach of the

Fio. 4o,. Digrams illu.tr.um, ,!„ i „ ,,, the 4 primitive medusa and not connected with the gas- genital cavities (A) to Form a angle cruciform cavity (c).

trovascular cavity, but opening to the

surrounding ocean through the 4 interradial genital ostia. The formation ot this cmcifnim, genital cavity, or subgenital porticus of I laeckel, is illustrated in the 3 diagrams of figure 401. In A, we see 4 separate, interradial, genital sacs ((/') projecting into the stomach-cavity (.S'l, as in Rtiizostoma and Cassiopea. In B we see these 4 sacs fused at their inner ends as in some species of Cfphea (Netrostoma); and in C we hnd the walls broken down in the fused regions forming a cruciform genital space lying beneath the stomach as in Cotylorhiza, Crambessa, Mtiitigiiis, etc.

The umbrella of the Rhizostonitc resembles that of their more simply organized ancestors the Semsostomeae. It is usually dome-shaped and covered with nematncvst -waits. The In II- *Eiccpting in Loboncma, gen. nov., wherein the marginal lobes are converted into long, tapering tentacle-like organs.

632 MEDUS.E OF THE WORLD.

lappets and rhopalia are in all respects similar to those of the Semaeostomeae. The muscular system of the subumbrella is well-developed and these forms are usually vigorous swimmers, although in Cassiopea we find that the medusae commonly remain upon the bottom with their oral sides uppermost, and the pulsations of the umbrella serve mainly to stir up currents which may bring food to the mouths.

At the center of the subumhrella we find a thick, disk-shaped, gelatinous projection called the arm-disk, for the 8 adradial mouth-arms arise from its lower side. This arm-disk is merely the lower wall of the stomach which has become thickened in order to give support to the heavy gelatinous mouth-arms. In all forms, however, having a unitary, cruciform, genital cavity, an open space lies between the arm-disk and the stomach so that the arm- disk is suspended from the subumbrella by 4 thick perradial columns which are separated one from another by the 4-rayed genital porticus, which opens to the outer world by 4 inter- radial ostia which alternate with the columns.

The cruciform, central stomach dips downward into these perradial columns and 4 bifurcated or 8 simple canals arise from the stomach and extend downward into the 8 adradial mouth-arms, giving off numerous branches to the mouths. The 16 canals to the scapulets, when these are present, arise from these 8 mouth-arm ducts, as do also the canals to the arm-disk, which fuse into 4 and finally into a single, central duct at center of arm-disk. The central stomach also gives rise to canals which radiate outward through the subum- brella of the bell. These may be connected by one or more ring-canals, or by networks of anastomosing vessels.

The facility with which some of these medusas may be maintained alive in aquaria has permitted certain physiological work to be performed upon them. Bethe, 1903, 08, 09, studied the rhythmical pulsation of Cotylorhiza and Rhizostoma, and Mayer, 1906, 08, carried out experiments upon Cassiopea. Bethe finds that the pulsation resembles that of the verte- brate heart in all important respects. The pulsation-stimulus is nervous in nature, and the "all or none" principle applies to medusae as it does to the vertebrate heart, as does also the phenomenon of the refractory stage of Marey, 1876. A definite interval of time elapses between the passage of the nervous stimulus and the response of the muscles, and the pulsation is a reflex due to a constantly present stimulus, the response to which is periodic, because after the nerves have responded to the stimulus they become incapable of reacting to it until after a definite interval of rest, this resting period being called the refractory stage.

Bethe, 1908, 09, in his study of Rhizostoma pulmo comes to conclusions in respect to the effects of the ions of sea-water upon pulsation, which are in accord with those of Mayer, 1906. (See Rhizostoma pulmo.}

Mayer, 1906, 1908, working upon Cassiopea, found that the sea-water is a balanced fluid, neither stimulating nor inhibiting pulsation. This is due to the fact that the stimulating effect of the sodium ion of sea-water is counterbalanced by the inhibiting influences of the calcium, potassium, and magnesium. The stimulus which produces pulsation is due to the constant maintenance of a slight excess of the sodium cation in the marginal sense-clubs, over and above its concentration in the surrounding sea-water. This excess of sodium is main- tained by the constant production of sodium oxalate in the terminal entoderm of the sense- clubs. This oxalate precipitates calcium to form the calcic oxalate crystals of the sense-club and sets free sodium chloride the sodium ion of which acts as a nervous stimulant. Details of these researches upon pulsation are given in the accounts of Cotylorhiza tuberculata, Rhizostoma pulmo, and Cassiopea xamachana.

Hargitt, Zeleny, and Stockard have studied regeneration in Rluzostornie. Zeleny stated that in Cassiopea the greater the number of arms removed up to 6 the more rapidly does each and every arm regenerate, but this is refuted by Stockard, who further shows that the regenerating tissue has a greater ability to absorb nutriment than have the normal, somatic body tissues, and that in consequence of this the body shrinks in size in direct proportion to the growth of the regenerating arms, the growing arms reducing the body as do cancer cells in their prolifer- ation. Stockard also shows that cuts near the center regenerate more rapidly than those near the margin of the disk, this being in accord with Morgan's law that the deeper the level of the cut the more rapid the rate of regeneration. In Rhizostoma pulmo Hargitt found that two rhopalia sometimes regenerate in the place of one which he had removed, and I have observed

HHI/nvniVli:. li.'l.'l

the same thing in f .'<;<>/<,/>,<(. In C.n.\ wo/>,-i; \,im,i. h,ui,i R. P. Bigelow showed that the rhopalia an- derived from every alternate tentacle of tin- so phostoma. the other tentacles degenerating wholly. I find that in this medusa when the ihopalium regeneraics it gives rise to a short latcial branch thus tending in an abortive manner to regenerate the tentacle, fi»m which it originally came.

Many observations have heen cairied our upon the emhi\o|i>gy of Rhi/.ostomae, and reviews ot these researches will he found in the descriptions of Cassiopea xamachana, Cotvl- orhiza tuberculata, Rhtzostoma pulm'i, Mastigiai /><;/>;/<;, Phyllorhiza f>iin<-tiit<i, and St'inm- lnf>/iiis wi-lt-tivris. Clans. Goette, R. P. Bigclow, Kowalevsky. \oii Lendenfeld, and Vanhntfcn have heen especially active in these it-searches.

Haeckel, 1880, considered the presence or absence ot a unitarv, cruciform, genital cavity to he of great systematic importance and sought to separate families upon this distinction; hut Claus, von Lendenfield, Vanhotfen, Maas, and Browne have demonstrated that this is a matter of no great import, tin in different individuals of ihe .same species we nun find in some cases 4 separate genital sacs, while others have a crucilmin genital cavity, and still others may have a more or less complete coalescence and breaking apart of the partitions m some quadrants and not in others. It is therefore evident, as was first clearly shown by Claus, 1883 (Oin.in- isation und Entwick. Medusen), that the conditions exhibited by the genital sacs afford no criteria for the distinction even of genera, much less of families. Indeed, Haeckel 's svstem leads to the separation ot closely related forms and the close approximation of remotely related forms, and is quite artificial.

Claus, 1883, 1886, and Vanhiiffen, 1888, have attempted to separate the families of Rhizostomae upon the distinctions afforded by the manner of branching of their mouth-arms. Claus's system somewhat modified by von Lendenfeld, 1888 (Zeit. fur wissen. Xool., Bd. 47, p. 208), distinguished nine families as follows:

RmzovroM.t;: Scyphomedus.T without marginal trntaclrs and with 8 adnuli.il mouth-arms.

Archirihizid.F: Mouth-arms unbranchcd. Gastrovascular network simple. No central mouth.

Cassiopfitfa: Arm-disk flat. Arms long, irregularly branched with appendages. Radial-canals numerous. No central mouth.

Craunostoinldtf: Arm-disk wide, style-shaped, arms dichotomously forked. Arm-margins free, with clubs. Ccntn| - tl] canals end blindly. Subgenital porticus unitary. Central mouth-opening present.

CepheiiLt: Arm-disk wide and flat. Arms dichotomously forked, w ith 2 of the axial, terminal wings turned outwards. VA "ith clubs. No direct central mouth-opening.

LychnorhizliLr: Arms j-leaved or distally 3-winged. 8 or 1 6 radial-canals. Gastrovascular network simple. No central mouth.

StomolophitLf: Arm-disk style-shaped, elongate, with 8 pairs of lateral "shoulder ruffles" or "scapulets." Proximal parts of the arms fused into a tube, distal parts branched. 16 radial-canals, with well-developed net-work of con- necting vessels. No central mouth.

RhizoslomnLr: Arm-disk style-shaped, elongate, with 8 pairs of lateral "scapulets" with clubs. Lower-arm three- winged, with dorsal mouths. 16 radial-canals. Centripetal network of canals well-developed. X" u-ntr.il moulh.

Caiosi\lidii: Arm-disk very wide, elongatei and style-shaped. Lower .irrn v^inged with dorsal mouths. Nocentrip- etal networks uf canals. Subgenital porticus uniturv. No central mouth.

Ltptobrachid*: Arm-disk wide and fused with the upper arms. Lower arms long, ribbon-shaped, and 3-winged. Simple canal net spread over the entire subumbrella. Subgenital portitus unitary. No central mouth.

A simpler system is proposed by VanhiiHen, iSS8 (Bibliotheca Zoologica, Heft 3), who divides the Rhizostomte into 7 families:

Rhizouomata sitnplicia: Mouth-arms Bimplc and unbranchcd. All of these are apocryphal, having been seen only

hv Hactkel and I'Ywkrs.

Dicholoma: M<iuth-arms dichotomously forked, with lateral expansion .. Pinniita: Elongate mouth-arms pinnately or irregularly branched. Triptera: Mouth-arms ^-winged. Each mouth-arm with a ventral and 2 dorsal lamella? which meet at a point at the

lower end of the arm.

Trigona: Identical with the Rhizostornata Irifttera. Lorifera: Mouth-arms elongate, lash-like, and triangular in cross-section; with mouths developed along the 3 angles

of the arms. Xmfulaia: Mouth-arms with simitar-shaped "scapulets" or "ruffles" projecting from their dorsal sides.

As was pointed out by Maas, 1903, Vanhoffen's Triptera and Trigona are identical and should be united, thus reducing his families to six. Schultze, 1898, showed that the mouth-arms of the " Dichotonni " of N'anhiiffen are not forked at their outer ends, but uive rise to ^ broad, longitudinal, lutrnil lamella?, which may branch secondarily. With these modifications Vanhoffen's system affords the readiest means of classifying the Rhizostomae, being based upon the mutations of the most conspicuous organs, the mouth-arms.

634 MEDUS/E OF THE WORLD.

Maas, 1903 (Syphomedusen der Siboga Expedition, p. 89), proposes another system based upon the character of the muscle-system of the subumbrella, the presence or absence of ocelli on the sense-clubs, the character of the canal-system and of the mouth-arms. Maas's system is as follows:

Arcadomyaria: The subumbrella muscles are arranged in feather-like arcs. Mouth-arms elongate and irregularly pinnate in their branching. Rhopalia with ocellus and without an exumbrella sensory pit. Radial-canals twice as numerous as the rhopalia and connected by an anastomosing network of vessels. One or more ring-canals may or may not be present. 4 separate genital sacs, with small, round, interradial ostia. There is only one family, the Cassiopeida.

Radiotnyaria: Radial-muscles of the subumbrella better developed than the circular muscles. Mouth-arms bifurcated. Rhopalia without ocelli and without exumbrella, sensory pits. 8 principal and other secondary radial-canals, all connected by a marginal network. No definite ring-canal. Funnel-shaped genital ostia. A unitary subgenital cavity may or may not be present. There is one family, the Cepheidt?.

Cyclomyaria: Circular muscles of the subumbrella better developed than the radial-muscles, the latter being often absent. Mouth-arms 3-winged, or derived from this type. There are 3 groups of the Cyclomyaria, as follows:

(-4) 16 radial-canals which extend from the stomach to the bell-margin, and between them a blindly-ending, anastomosing network of vessels. Mouth-arms with scapulcts. Genital ostia slit-like and divided by a median flap. Rhopalia without ocelli, but with sensory pits with radiating furrows. Group A is equivalent to the Rhizostonitdtf+ Stomo- lophidd: of Claus, or to the Rhizostomata scafiulata of Vanhbffen.

(5) 8 rhopalar canals extend to the bell-margin and 8 in the inter-rhopalar radii end in the ring-canal. On its outer side, the ring-canal gives off a network of anastomosing vessels, and on its inner side it gives rise to another network which ends blindly without connecting with the stomach.

(1) Mouth-arms j-winged, usually with pinnate lateral brandies. Genital ostia slit-like. Rhopalia with pigment spots, and sensory pits with radiating furrows. This contains the family Lychnorhizidts of Claus; including the genera Lychnorhiza, Crambione, and Crambessa.

(2) Mouth-arms very elongate, triangular in cross-section. Genital ostia wide openings. Rhopalia with pigment spots and furrowed sensory pits. This contains a part of Claus's family Leptobracht'dtf.

(C) The 8 rhopalar extend to the bell-margin, and (8X«) canals extend only to the ring-canal. On its outer side the ring-canal gives off a narrow network and on its inner side is a network of wider mesh.

(1) Mouth-arms very elongate, triangular, file-shaped. Genital ostia wide slits. Genera: Thysanostoma, Lepto- brachia, and Himanostoma of Claus's Leptobrachidae.

(2) Arms j-winged, not elongate. Ostia wide. Rhopalia with ocelli and small sensory pits without furrows.

This is equivalent to Claus' family Catostylidcs containing the genera Loborhiza, Crossostoma, and Mastigias.

The Arcadomyaria of Maas is only a new name for Vanhoffen's Rhizostomata pinnata, the Radiomyaria are equivalent to Vanhoffen's Rhizostomata dichotoma, and the Cyclomyaria includes rather confusedly the trtpt era -\-tngona-\- scapulata -\-lonf era of VanhofFen. Maas's system is erroneous in some respects; for example the rhopalia of Casswpea xamachana have pigment spots while those of Casswpca frontiosa have none; similarly Crambessa tagt has ("ocelli") pigment spots but Crambessa mosaica has none. It is therefore evident that the presence or absence of "ocelli" does not afford a suitable criterion for the separation even of genera. The exumbrella sensory pits may have furrows, in one species of a genus and be simple in another, as in Rhopilema esculent a and R. verillii. In my opinion the older and simpler system of VanhofFen is to be preferred to this complex scheme proposed by Maas.

In view of the observations of Schultze and of Maas, we may amend Vanhoffen's system as follows:

Rhizostomata pinnata; Rhizostomae with 8 separate, elongate, linear mouth-arms which give rise to pinnately or com- plexly arranged side branches (figs. 4, 5, and 7, plate 69). The circular muscles of the subumbrella tend to be bowed outward in a series of arcs on both sides of each radial-canal, the convexities alternating with the canals. The genera are as follows: Torcutna HA ECKEL, 1880, with 8 rhopalia.

Cassiopea PERON AND LESUEUR, 1809, with more than 8 rhopalia.

Rhizostomata dtchotoma: 8 separate mouth-arms, the lower parts of each one of which is V-shaped in cross-section, the apex of the V being centrad, and the rays directed outward (fig. 404, p. 650) The mouths are developed upon the ventral sides of the mouth-arms. The radial-muscles are powerfully, and the ring-muscles weakly, developed. The radial-canals are all connected by a marginal network of vessels, without a definite ring-canal. The genera are as follows:

Cephea P£RON AND LESUEUR, 1809. Exumbrella with a central dome bearing solid, wart-shaped protuberances. Cotylorkiza L. AGASSIZ, 1862. With a smooth, simple dome at the center of the exumbrella. Polyrltiza L. AGASSIZ, 1862. Exumbrella with a central depression and with radiating furrows.

Rhizostomata triptera: 8 separate mouth-arms the lower parts of each of which is Y-shaped in cross-section, due to the development of 2. lateral, dorsal, and a median ventral, longitudinal lamella, all 3 of which taper to a point at the lower end of the arm. The mouths are developed upon the free edges and partially over the sides of the 3 lamellae or wings of the mouth-arms (fig. 41 1, p. 664) The ring-muscles are powerfully and the radial-muscles weakly, devel- oped. A ring-canal with a network of anastomosing vessels arising from its inner and outer sides is usually present. Mouth arms without scapulets. The genera are very closely related and are as follows:

Catostylus L. AGASSIZ, 1862= Toxocl\tus+ Crambessa HAECKEL. Mouth-arms without filaments, clubs, or other appendages. The network of vessels arising from the inner side of the ring-canal ends blindly, without con- necting with the stomach.

Lychnorhiza HAF.CKEL, 1880. With filaments but without clubs upon the mouth-arms. In other respects similar to Crambessa.

iiHizosTOMjE — TURKU MA. r»;j;»

Rhizottomata fripttra, continued —

Crambione MAAS, 1903. Similar to Crambcua, but with both clubs and filaments upon the mouth-arms. Masttgias L. A'.ASSIZ, iS(»i .Miiitii>ias + Kucrambessa HAKKM. Each rnouth-arm terminates in a naked club. Numerous clubs or filaments among the mouths. The network of vessels which arises from the inner side of the ring-canal connects with the stomach.

Pitudorhiza VON LtNiii.Nt I.LD, 1882. Similar to .\fastigiat but without lateral clubs or filaments upon the mouth-arms. A terminal club present. The canals which arise from the circular vessel, between the radial- canals end blindly without reaching the stomach.

PhyJlorhha L. AGASSIZ, 1862. Mouth-arms with lateral filaments, but without clubs as in Lychnorhiza. Canal- system as in Mastigias. Vessuru, HAM KM., 1880. Mouth-arms with clubs and filaments as in Crambione. 4 perradial canal

directly from the stomach, but the 4 interradial canals result from the fusion of a network of vessels which arise from each interradial side of the stomach. An outer and an inner zone of circular muscles with an annular separation between them. Lobonftna, gen. nov. Marginal lappets elongated to form tentacles-like organs. Mouth-arm membrai:

orated by window-like openings. Exumbrella covered profusely with papill.r.

Rkisostomata lorifera: 8 mouth-arms, very elongate, whip-like, and triangular in cross- sect ion, with frilled mouths developed along the angular edges of the arms (fig. 4 117, p.(nji ! Thc( \ lmdric.il upper parts of the arms are rudimen- tary and partially fused one to another by gelatinous arches spanning between them and connecting them \uih arm-disk. The genera are as follows:

Thysanostoma L. AGASSIZ, 1862. No terminal clubs on the mouth-arms. Mouths along the 3 angles through- out length of arms.

Lorifi'f/i, \\\\< KM., iSSo. Similar to Ttn'sanostoma, hut with a naked club at lower end of each arm. Lefitobrachiii BRANDT, 1838= Lfptobrarhia -t- Leonura HAI.CKI i . M< milr-. confined to the upper and lnv i

of the mouth-arms, leaving the middle part of the arm naked.

Rhizostomata srapulata: Each mouth-arm bears a pair of simitar-shaped .ip(" ii.l.u-r ( i.ipulrt I which arise from tin- outer side near the base of the arm and bear frilled mouths (fig. 421, p. 697). The circular muscles of the sulnimhn II a are powerfully, and the radial-muscles weakly, developed, or even absent. The genera are av (..!!••

Rhbustoma CUVIKR, iBoo^Piltma HAK.KKL, 1880. 8 free mouth-arms, the lower parts of which are Y-slnped, or 3-wingcd, in cross-section. Each arm terminates in a naked club. There are no other clubs or filaments. Rhopiicrrut HAM KM, iSSo. Similar to Rhizostoma but with numerous clubs or filaments upon tin* mouth-arms. Euftilema HAKCKKL, 1880. Similar to Rhizostoma, but the arms have neither clubs nor filaments. Stomohpkui L. ACASSIZ, \$()2=BrachiolQf>hus+StomoIof>hus) MA>CK>I, iSSo. The 8 mouth-arms ai-

along their sides leaving only the lower ends free and forming an < luiHMie throat-tube for the ti-ntr.il mouth which remains open. Rhizostomata simplicia: Rhizostoma' with unbranched mouth-arms. These apocryphal forms arc described by H

and by Fewkes from alcoholic specimens of small size. They are apparently immature or injured specimens. V* naturalist lias seen any of these forms since Fewkes described Ins " Xivmotontma rtticulatum" in iSS4_ It is probable that we should drop these medusa? from further consideration, but in the faint hope that some may be discovered I have given descriptions of them based upon the statements of Haeckel and Fewkes.

RHIZOSTOMATA PINNATA Vanhbffen.

Rhizostomata pinnata, VANHOFFKN, 1888, Bibliothcca Zoologica, Bd. I, Heft. 3, p. 40. — MAAS, 1903, Scyphomcdusen der Siboga

Kxped., Monog. n, p. 38. Cassiopeidat CLAUS, 1883, Organisation und Entwick, Medusen, Leipzig. — VON L>M»M n n, 1888, Zeit. fur \vissen. /.""I.. H.I.

47, p. 211. Arfadomyaria, MAAS, 1903, Scyphomcdusen der Siboga Exped., Monog. n, p. 88; 1907, Ergeb. Portschritte der Xool., Bd. i,

p. 201; 1906, Revue Suisse de Zool., tome 14, p. IOO.

Rhizostomous medusae with 8 linear, pinnately, or complexly branching mouth-arms.

GENERA.

Toreuma Haeckel, 1880. 8 rhopalia.

Cassiopea Pcron and Lesueur, 1809. More than 8 rhopalia.

Genus TOREUMA Haeckel, 1880.

Toreuma, HAECKEL, 1880, Syst. der Medusen, p. 566.— VANHUFFEN, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, p. 40.- M \->- , 1903, Scyphomcdusen, Siboga Exped., Monog. n, p. 43.

The type species is Toreuma dieuphilay described by Peron and Lesueur from the Indian Ocean.

GENERIC CHARACTERS.

Rhizostomata pinnata with 8 adradial, linear mouth-arms which branch pinnately or complexly, and the main side branches also branch. 8 marginal sense-organs.

This genus is closely related to Cassiopca and is distinguished only by having 8 rhopalia, whereas Cassiopea has more than 8. Haeckel is the only modern naturalist who has seen any of these forms. They all come from the Indian Ocean.

MEDUS/E OF THE WORLD.

Toreuma dieuphila.

Cassiopea dieuphila, PERON ET LESUEUR, 1809, Annal du Mus. Hist. Nat. Paris, tome 14, p. 356.

Cassiopea thtophila, DE LAMARCK, 1816, Hist. Nat. Anim. sans Vert., tome 2, p. 511.

RhKosloma thtophila, ESCHSCHOLTZ, 1819, Syst. der Acalephen, p. 53.

Pol\clotnia thtophila, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 159.

Toreuma theophila+ T. lhamnosloma+T . gegenbauri, HAECKEL, 1880, Syst. der Meduscn, pp. 566, 567, 645.

It is probable that Haeckel's T. " thamnostoma" and "T. gegenbauri" are only growth- stages of Peron and Lesueur's "Cassiopea" dieuphila. I therefore present the descriptions of the three forms side by side in order that they may readily be compared. Haeckel enjoyed the opportunity of studying Peron and Lesueur's original specimen preserved in Pans.

	Toreuma dieuphila= Cassiopea dieuphila Peron and Lesueur.	Toreuma "gegenbauri" Haeckel.	Toreuma "thamnostoma'' Haeckel.
Diameter of bell in	60 to 80	60	90
mm.
Shape of bell.	Hemispherical (contracted?)	Flatter than a hemisphere, without	Flatter than a hemisphere. Exum-
	Exumbrella with coarse warts.	papillae.	brella with small warts.
Number of marginal	96. In each octant 10 short,	80. In each octant 8 short, rec-	1 20 to 1 60. In each octant 1 4 to 1 8
lappets.	rectangular, velar, and 2 very	tangular, velar, and 2 very small,	short, rectangular, velar, and z very
	small, ocular lappets.	ocular lappets.	small ocular lappets.
Length of mouth-	Less than r long (contracted ?)	I to 0.5 r long.	Nearly 2 r long.
arms in terms of
bell-radius (r).
Number of branches	6 to 8 wide, flat, main side-	8 to 12 flattened main side-	12 to 16 cylindrical, main side-
of each mouth-arm.	branches.	branches.	branches.
Appendages upon	Numerous small, and 10 to 20	Numerous small clubs and a very	Numerous club-shaped vesicles.
mouth-arms, be-	large, club-shaped vesicles.	large one at base of each arm,	Smoother than in T. dieuphila,
tween mouths.		half as long as arm itself.	and not longer than width of mar-
			ginal lappets. (Large clubs lost ?}
Color.	Bell brownish-red, with white	Bell brown (?) An elongated,	Bell dark-brown with numerous
	spots on the lappets. Gonads	white spot upon lappet.	white spots. Abaxial surface of
	and clubs white.		arms yellowish-brown. Clubs
			white.
Where found.	Northwest coast of Australia,	Tropical Indian Ocean.	Indian Ocean.
	in the Indian Ocean.

Genus CASSIOPEA Peron and Lesueur, 1809.

Cassiopea, PERON ET LESUEUR, 1809, Ann. du Mus. Hist. Nat. Paris, tome 14, genre 24, p. 356. — ESCHSCHOLTZ, 1829, Syst. der Acal., p. 42. — TILESIUS, 1834, Acad. Caes. Leop. Nova. Acta., torn. 15, p. 256. — BRANDT, 18^8, Mem. Acad. Imperiale des Sci., St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 396. — GUPPY, 1883, Nature, vol. 27, p. 31 (habits). — VON LEND ENF ELD, 1884, Proc. Linnean Soc.New South Wales, vol. 9, p. 284. — CLAUS, 1883, Organisation und Entwick.der Medusen, p. 60. — COLASANTI, 1886, Atti Acad. Med. Roma, Anno. 12, 18 pp. (blue color). — AGASSIZ AND MAYER, 1899, Bull. Mus. Comp. Zool. at Harvard College, vol. 32, p. 175. — KELLER, C., 1883, Zeit. fiir wissen. Zool., Bd. 38, p. 632. — BROWNE, 1905, Fauna and Gcog. Maldive and Laccadive Archipelagoes, vol. 2, p. 966. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. u, pp. 38, 80. — SCHULTZE, L. S., 1898, Abhandl. Senckenberg. Gesell., Bd. 24, Heft. 2, p. 163.

Cassiopea+ pol\clonia, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 139, 155, 159. — PERKINS, 1908, Papers from Tortugas Laboratory of Carnegie Inst. of Washington, Publication 102, p. 150.

Polyc/onia + Cassiopea, HAECKEL, 1880, Syst. der Medusen, pp. 567, 568.

The type species is Medusa andromeda Forskal, called C. forskalca by Peron and Lesueur ( = C. andromeda, Eschscholtz) of the Red Sea and Indian Ocean. The first species des- cribed by Peron and Lesueur, 1809, is called Cassiopea dieuphila. Haeckel, 1880, however, places this in the genus Toreuma.

GENERIC CHARACTERS.

Rliizostomata pinnata with 8 (4 pairs of) adradial, complexly branched mouth-arms the lower or ventral surfaces of which hear numerous mouth-openings and vesicles. There are 4 gonads and 4 separate subgenital cavities. There are more than 8 marginal sense- organs and twice as many radial-canals as sense-organs. The radial-canals are placed in communication one with another by means of an anastomosing network of vessels. A definite ring-canal may or may not be present.

IUIIZOSTOM/E— CAssmi'KA. c,:;7

Tilesius, 1834, figured 4 species of Caisiofea and represented each of them as having 8 subgenital cavities. Relying upon the figures of Tilesius, L. Agassiz, 1862, separated the genus Polyclonia, having but 4 subgenital cavities. Later researches have demonstrated that all the known species of these medusae have normally hut 4 subgenital cavities, and should therefore be placed in tin- s;enus Cassiopea. llaeckel, 1880, attempts to separate Cassiopea from Polyclonia by calling medusas with 16 marginal sense-organs Casa while those with 12 of these organs are called Polvcl'jniii. The nutnl>,r of marginal sense- organs is, |IO\\I-\I.T, vciv variable, not onl}' among different species of these medusa: but also among individuals of the same species, and therefore can not be used as a means of establish- ing generic distinctions.

The medusae of this genus are all inhabitants of warm oceans, and are found in gn.it< st abundance in the tropical coral regions nf the Hast Indies and Red Sea. R. 1'. Bii>elo\\ finds that (',. xamachana from the \\Yst Indies develops through the monodiscus strohili/ation of a scyphostoma and the young ephyrae of this species and of 6'. fronJosa have a simple, central, ^.-cornered mouth, thus recalling the adult condition in the Sein.eostonu.i-. from \\hich forms the Rhi/ostom;e have evidently been derived. The rhopalia of the ephyra are derived from the bases of each alternate tentacle of the scyphostoma, the other tentacles degenerating.

1 he number of "species" of Cassiopea has been multiplied greatly, owm«; to the remark- able color-range and variability in other respects of these medusae. These color types appear to be local, and the Cassiopea medusae of almost everv new region of the tropics are nearly certain to be described as "new species" based on color peculiarities. It is therefore impos- sible, at present, to classify the forms of Cassiopea with any degree of certainty.

The blue and amber-green coloration of these medusae is due to the presence of com- mensal plant organisms. Colasanti, 1886, describes the blue pigment matter as zoocyanin.

Maas, 1 903, at tempts to separate the genus into two cohorts; one, consisting of (',. in, it, »;./. C. tnertt-nsi var. ndrosia, polypotdes, xamachana, 'jinnt<i. and ornata var. Jigitata, distinguished by its long, cylindrical, pinnately branched mouth-arms. The other group consists <>f ('.. andromeda ami its varieties: C. deprcssa and (]. il<-pr?ssti var. />/./<;. This latter cohort has irregularly branched, short, flat mouth-arms. An idea of the range in color-patteins uf these medusas may be obtained from an inspection of plates 70 to 72 which exhibit photographs ot a tew of the varieties of Cassiopea xamachana, all taken in the course ot ;ni hour tmni the moat of Fort Jefferson, Tortugas, Florida.

Stockard demonstrated that in ('.. xamachana the nearer the injury is made to the crnici of the disk the more rapid the rate of regeneration. He also found that the more arms we remove, the more does the central disk shrink dining the growth of the ICLK ru i .it inu arms, and he thus finds that the regeneratm;; tissue absorbs nutriment at the expense ot the normal body tissue as do cancerous tissues in then orovvth.

Mayer finds that the rh\ thmical pulsation in ('.. \nm, i, li,ni,i is due to a nervous stimulus, and this stimulus is caused by the presence of a slight excess ot sodium in the rhopalia over and above the concentration ot this ion in the surrounding sea-water. This excess ot the sodium

D

ion is due to the constant tormation ot sodium oxalate in the sense-club, and this oxalate precipitates the calcium chloride of the sea-water to form the calcium oxalate ci vst.ils of the sense-club and sets free sodium chloride.

R. P. Biuclow finds that the vesicles between the mouths of C. fronJosa serve to capture prey and to thrust the food into the mouths.

Cassiopea andromeda Eschscholtz.

Medusa andromtda, FORSKAI , 1775, Dcscript. quc in It inert- Orient all Ol>M-rva\ it, Mauni.r, p. 107, tab 31 , ^ fii^n.

Cassiopfa andromcdti, KSCHSCHOLTZ, iSii), S\ i . ,1< r Ai .ilrphcn, p. 43. TIMMIS, rX:<i. ' \1--n. N. C.. l->mc i >,

p. 266, taf. 69, 70. Mits>-r.n\v\Ki», 1849, Curier's Rigne Animal DIunH, Zoopb., plate 51, tii;. I.- HMCWM. i"» .

Sjst. der Meduscn, p. 569. Kfii»n. iSS8, Zool. Anzcigcr, BJ. 11, pp. 359, 389. — Hjrtl.mli, i»jo», /.»»li,i;. (.ihrt'inh'T.

Abtll. Syst., H.I. l-J, p. 467, taf. n, fii;n. l-S. Cassioftea jorskalta, P£RON vi I.IM hi K. i Soq, Annal. du Mus. Hist. Nat., Paris, lomc 14, p. 356.

Bell flat, shield-shaped, IOO to 120 mm. wide, 20 to 30 mm. high. 15 to 18, usually [6, marginal sense-organs. A variable number of short, blunt lappets. In each p.nameie are I to 6, usually 3, velar flanked In 2 ocular lappets. 8 mouth-arms, wide. flat, and hardly as long as

638

MEDUSvE OF THE WORLD.

Synopsis of the Described Forms of Cassiopea.

	C. andromeda	C. andromeda var. zanzi- barica.	C. andromeda var.malayen- sis.	C. andromeda var. maldiv- ensis.	C. andromeda var. acyclob- lia.	C. polypoides.	C.xamachana.
Shape of bell.	Flat.	Flat.	Flat.	Exumbrella	With low cen-	Sucker-like	Exumbrella
				concave.	tral dome.	concavity on	concave.
						exumbrella.
Number of	12 to 18, usu-	16	16	12 to 19, us-	16	16	ii to 23, us-
rhopalia.	ally i A.			ually 16.			ually about
							16.
Number of	5, occasionally	S	3» 5> 7, or 9	70 to 10	5	5	5
marginal lap-	I to 6.
pets in each
paramere.
Length of	Less than r.	Less than r.	Less than r.	Less than r.	0.6 r	r+	I to 0.25 r
mouth-arms
in terms of
bell-radius(r).
Vesicles and fil-	Many small;	Many small,	Many small,	Linear, hand-	8 large, many	Large and	Large and
aments among	5 or more	<; large clubs.	2 to ^ large	shaped, and	small fila-	small clubs	small ribbon-
mouths.	large, club-	Longer than	clubs.	ribbon-	ments.	and filaments.	like filaments.
	shaped vesi-	in C. andro-		shaped ap-
	cles.	meda.		pendages.
				Some very
				large.
Where found.	East coast of	Zanzibar	Malay Archi-	Maldive Is-	A inborn a,	Coral flats of	West Indies to
	Africa, Red	coast, East	pelago.	lands, Indian	Malay Arch-	Red Sea.	Florida.
	Sea to the	Africa.		Ocean.	ipelago.
	Malay Arch-
	ipelago.

	C. frondosa.	C. ornata.	C. ornata var. digitata.	C, depressa.	C. depressa var. picta.	C. mertensii.	C. ndrosia.
Shape of bell.	Flat.	Flat.	Flat.	Flat.	Flat.	Rounded with-	Exumbrella
						out a concav-	concave.
						ity on exum- brella.
Number of rhopalia.	12	16	16	16	14 to 16	16	1 8 to 22
Number of marginal lap- pets in each	S	5	Variable, about 5.	9	Variable, 5 to 12 usually.	8	4
paramere.
Length of mouth-arms	0.75 r to r.	r +	i to 0.5	Less than r.	Less than r.	I to 0.5 r	I to 0.5 r
in terms of
bell-radius(r).
Vesicles and fil- aments among mouths.	Only flat leaf- shaped vesi- cles.	Very small clubs.	Very small clubs.	Very small clubs.	Very small clubs.	Very large clubs.	Small leaf- shaped vesi- cles.
Where found.	West Indies to Florida.	Pelew Islands, New Guinea.	Malay Arch- ipelago.	Coast of Moz- ambique, East Africa,	Red Sea.	Caroline Is- lands.	Fiji Islands.
				Madagascar.

bell-radius. 4106 flat, short side branches arise from each arm in a tree-like manner and these in turn give offside branchlets. Numerous small and 5 or more large, club-shaped vesicles on each arm between the mouths. The largest 2 to 3 times as long as width of main branches of arms. 4 small subgenital ostia.

Color very brilliant and variable. Exumbrella is reddish-brown to violet-brown, with milk-white spots, between which are dark, radial stripes. Bell-margin usually bluish or violet. The milk-white spots on the exumbrella are disposed as follows: A large oval spot above each sense-organ and a small, white spot upon each lappet. Thus there are 80 (5X 16) small

RHIZOSTOMyE — CASSIOPEA. 639

spots and 1 6 large ones, 96 in all. Mouth-arms olive-green to reddish-brown, spotted with white.

This East Indian species ranges from the Red Sea to Sumatra, giving rise to a numher of color varieties and local races, many of which have been described as distinct species. Keller, 1888, records its having wandered into the Suez Canal from the Red Sea. Hartlaub gives a good description of this species from Djibuti, East Africa.

Cassiopea andromeda var. zanzibarica Chun. Cassiopea andromeda var. zanzibarica, CHUN, 1896, Mittheil, Naturhistori&chcn Museum, Hamburg, Bd. 13, p. 17.

This resembles C. andromeda in most respects, being 40 to 90 mm. in diameter and with a flat disk. But it is said to be distinguished trom C. anJromeJa by having 6 velar and 2 ocular lappets between each successive pair ot sense-organs instead of 5 lappets as m the typical C. anJromeJa. The 5 large clubs or filaments of the arm-disk are also larger than in C. iniJro- rneda, being 10 mm. long. The color is also different, but quite variable. The exumbrella is usually brownish-red with 16 to 17 smoky-gray or white radial streaks, which commence at the outer edge of the central concavity of the exumbrella and fork over the lappets. Some speci- mens have 3 white spots over the velar lappets between each successive pair of sense-organs. Mouth-arms light whitish-red beset with small brownish-white clubs. The lai^i o-niial fila- ments are black. Zanzibar coast, July to August. This is certainly identical with ('.. andromeda,

Cassiopea andromeda var. malayensis Maas.

Cassiopeja andromeda var. mala\ensis, MAAS, 1905, Scyphomedusen der Siboga Expedition, Monog. it, pp. 40, 43; taf . 4, fign. 24-15,17-29,31-34; taf. n, fign. 98, 102; taf. 12, fig. 112.

This medusa is said to be distinguished by having I, 3, 5, 7, or more velar lappets between each pair of ocular lappets. Mouth-arms are slightly shorter than bell-radius and compressed dorso-ventrally. A few large, isolated, club-shaped appendages are between the frilled mouths, but these are not commonly found upon all of the mouth-arms. Indeed, there are usually only 2 to 3 of these large clubs upon the mouth-arms of any individual medusa. The umbrella may become more than 200 mm. in diameter, although such large specimens are rare. There are normally 16 small, marginal sense-organs, each containing an entodermal concretion and a distal pigment spot. Young medusae have about 32 ocular and 16 velar lappets, but as growth proceeds the velar lappets increase by division so as to become 3, 5, 7, or more tunes as many as in the young medusa. The mouth-arms are compressed dorso-ventrally, those of C. acyclobbia laterally. They branch quite irregularly, in a tree-like manner.

Both male and female medusae are described by Maas, who records numerous examples ranging from 10 to 200 or more millimeters in diameter. The medusa appears to be widely distributed among the islands of the Malay Archipelago. Color (?) It is evidently identical with C. andromeda.

Cassiopea andromeda var. maldivensis. Cassiopea andromeda var. maldivensis, BROWNE, 1905, Fauna and Geog. Maldive and Laccadive Archipelagoes, vol. i, p. 962.

The disk is about 75 mm. wide with a central concavity on the exumbrella. The mar- ginal sense-organs range from 12 to 19 but are usually about 16. The marginal lappets are very indistinct and range from about 7 to 10 between each successive pair of sense-organs.

There are 4 pairs of complexly branching mouth-arms which project slightly beyond the umbrella margin. The proximal branches of the mouth-arms are generally alternate in position, while those of the outer branches are generally dichotomous. There are numerous disk-shaped, flat, spatula-like appendages over the mouth-arms. These are adjacent to the oscula. There are also cylindrical or somewhat flattened linear appendages and hand-shaped appendages, which are almost leaf-like and may be 25 mm. long and 9 mm. wide. There are not more than 5 to 6 of these cylindrical or hand-shaped appendages on each of the 8 mouth-arms. At the center of the mouth-arm disk there is a single long appendage which may either be cylindrical or hand-shaped.

The 4 subgenital ostia are very small and triangular in shape, about 3 mm. wide. The gonads are similar to those of Cassiopea xamachana. The peripheral canal-system consists

640 MEDTJS.E OF THE WORLD.

of a radial-canal to each sense-organ and an equal number of intermediate radial-canals. These radial-canals are put into communication one with another by means ot an anastomosing network of vessels, without any distinct ring-canal.

The medusa is dark-green without spots or pattern of any sort. This green color is due to an infesting alga, one of the ZooxanthelLr. The chlorophyl is readily dissolved out in alcohol.

This medusa is abundant in muddy bottoms in shallow bays and back waters at Febidu, Maldive Islands, Indian Ocean. It is a well-marked variety of C. andromcda being distin- guished by the hand-shaped appendages on its mouth-arms.

Cassiopea andromeda var. acycloblia Schultze.

Cassiopeja acycloblia, SCHULTZE, L. S., 1898, Denkschrift.Med. Nat. Ges. Jena., Bd. 8, p. 459, taf. 33, fign. 2, 4, 6; taf. 34, fig. 15. Cassiopeja anilromeJa var. cyclobalia, MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. n, p. 40.

Bell flat with low central dome (?) at middle of the exumbrella. 16 marginal sense-organs and 80 (5X16) marginal lappets. Exumbrella flecked with 16 large, oval, radially placed, white spots above the sense-organs. A wide ring of white binds these spots together. There is also a small, white fleck on the exumbrella side of each lappet. Those of the interradial lappets fuse with the white ring. Mouth-arms only three-fifths as long as bell-radius. Diam- eter of arm-disk less than disk-radius. The mouth-arms branch dichotomously each with one large and many small filaments. Amboina, Molucca Islands.

Cassiopea polypoides Keller. Cassiopea polypoides, KELLER, 1883, Zeit. fiir wissen. Zool., Bd. 38, p. 632, taf. 36, 37, fign. 6-23.

Disk flat, shield-shaped, 100 to 150 mm. wide. A well-developed, sucker-like depression at center of exumbrella, the thickened, outer edge of which is 15 to 20 mm. inward from bell- margin. Margin of umbrella is thin, but at the center there is a disk-like thickening of the gelatinous substance of the exumbrella. There are 16 marginal sense-organs each with a red-brown ectodermal pigment spot and a terminal entodermal mass ot concretions. 80 short, rounded, marginal lappets, 3 velar and 2 ocular in each of the 16 parameres. 1 he thick mouth-arm disk is octagonal with 8 equal sides. The 8 mouth-arms are about as long as radius of umbrella and project beyond the bell-margin; they are somewhat higher than wide at their distal ends. Each arm usually gives rise to 3 pairs of alternately arranged, pinnate branches, with frilled mouths on their under sides. There are numerous clubs and filaments on the under sides of the mouth-arms, the largest filaments being over 30 mm. long. The 4 subgemtal ostia are small, oval, and elongated in a radial direction. Central stomach 4-sided. 32 radiating canals extend outward from the stomach, 1 6 to the sense- organs and 16 to intermediate parts of the margin; these 32 vessels connect one with another by an anastomosing network of vessels, but there are no specialized ring-canals.

Exumbrella light-brown with a broad, white ring which gives out 16 cog-wheel-like, forked branches on its outer edge in the radii of the 16 sense-organs. There is also a short, white, radial spot on the exumbrella side of each marginal lappet. 16 dull white, spoke-like pigment areas in the gelatinous substance of the exumbrella extend outward from the edges of the central thickening to near the margin in the radii of the sense-organs. The suctorial mouths are intense brown. Appendages and filaments of mouth-arms very variable in color, being sky-blue, greenish-blue, horny-yellow, translucent white, or rose-red. In one variety the exumbrella is olive colored with indistinct radiating spots.

Keller distinguishes five varieties based on color and differences in number of the mouth- arm filaments as follows:

Cyanea. With 5 or 6 large, sky-blue or green-blue filaments on each mouth-arm. The white oral tufts are numerous,

the clubs rarer. This is the commonest form.

Flava. The large filaments are twisted, never flattened, their color is horny-yellow or translucent. Common. Albida. The large filaments are twisted and white in color. Rare. Rosea. Exumbrella olive colored, radial spots indistinct. Some of the filaments are round, some flat, and of rose-red

color. Club-shaped vesicles rare. Rare variety. Herbacea. The mouth-arm appendages poorly developed. No filaments. The mouths of the arms large. Rare variety.

PLATE 69.

Fig. i. Cassiopea fronJosa, young medusa, natural size. From the bottom

of the moat of Fort Jefferson, Tortugas, Florida, July 10, 1905. Fig. 2. Cassiopea fronJosa. Half of exumbrella shown on the right, and halt

of the subumbrella on the left. Natural size. Moat of Fort

Jefferson, Tortugas, Florida, June 23, 1907.

Fig. 3. Sense-organ of Cassiopea fronJosa seen from subumbrella side. Fig. 4. Cassiopea xamachanti, side view, natural size. From moat of Fort

Jefferson, Tortugas, Florida, July, 1905. Fig. 5. The mouth-arms of Cassiopea xamachaua, showing side walls of

stomach cut across. The canal-system in the arms is shown in

green. Fig. 6. Sagittal section of Cassiopea xamachana, showing stomach cavity.

The gastrovascular canals are shown in green. Fig. 7. Cassiopea xamachana. One of the mouth-arms cut off so as to show

the branching of the canal-system. Fig. 8. Cassiopea xamachana. Cross-section of a mouth-arm near its base

showing the fringing tentacles of the mouths and the shapes of

the appendages.

Drawn from life, by the author.

PLATE 70.

Fig. i. A rare, small-sized variety of Cassiopea xamachana. In its color- pattern this resembles Cassiopea ndrosia from the Fiji Islands. Fig. 2. The common color-pattern of Cassiopea xamachana.

Cassiopea xamachana photographed from life, from specimens found in the moat at Fort Jefferson, Tortugas, Florida, July, 1905. Natural size.

MAYER

PLATE 70

*

>

PLATE 71.

Cassiofea xamachana, photographed from life, by the author, natural size, July, 1908. From the moat at Fort Jefferson, Tortugas, Florida. Oral and aboral views of the medusa.

Klll/i iSTHM.K rASSIul'i: \. tl II

I his medusa \v;is found in lar»e swarms In Keller on the shallow coral Hats ol the southern parts of the Red Sea. Ir dirrers from i lie M pical (.. anJromeJa in the thick-rimmed sucker ot the exumbrella, and die long, laterally compressed arms. Keller describes it in detail with JMMX! figures. In common wiih other C'assiopmke it lies upon the boMoni with its oral surface uppermost. Keller draws comparisons between its habits and structure and those ot actimans, etc. This medusa is probably only a local variety of ('.. undrrniu-Jn, but the thick, sucker- like disk at the middle of the exumbrella appears to distinguish it.

Cassiopea xamachana R. P. Bigelow.

Plate 'MI, ti • | 'o X; plates 70 and 71; plate 72, tin- *-ven lo.'.-r h

C.iixivfx-ii \nni(i< htin,!, Hi>. new. K. P., iSij2, Zooloi;. An/eiqrr, Bd . i ^, p. 212; fohns Hopl.ins I'niMTMty Circular*. 1X92, MI|. ll, pp. 71, 84; 189^, Journal Institute of Jamaica, vul. i, p. ',01, i plate; 1900, Memoirs Boston Soc. Nat. Hi •., M'|. ?, NIL 6. p. 191, hi; . \ in I.. pl.iti ;i in ;X, 66 figs.— PI:RKINS, 1905. Year Book of the Carnegie Institution, No. 4, p. i iX. Publication, NCI. 102, p. 150, plate 4. MAIKK, ii|O'», Year Rook of tin- Carnegie Institution, Ni>. 4, p. 117; Publuation nf lln- Carnegie In^itution, No. 4-, (12 pp. (rlutlimical puhation); 1907, Year Itook ('.ini'-L-i'' lir ritufmn. Nn. fi, p. 121; [hi<t., i<)oX, No. 7, p. i;;. MA*V, i>to\. Si \ pli-nui ,|IIMTI I-T A//Ky»,i Kxpedition, Mmi"'. ii. p. 40. STOCKMU>, l«»o~, ^ i .11 Hunk t'.iincL'i'' In tiuitinii "t \\ .1- liiiifi'iii, N". d. p. MI) (regeneration)] Ihid., No. 7, 1908, p. i;o. — Papers from TorhitM J.alioi.it.in i if t'arni'Kii- IriMitutinn ol \\aslnni;!. m, vol. 2. p. 61, fit;!.. l-2!»; Journal of KxpiTinii ntal X,!-.|nf\. M|O»j, vi ii. Ii, p. 4;;, S hr . /i i i N t , t .. ii)O^. [oiirna! Kxprrimi-nta! Zoology j • "1. S, p. 2l»;, 4 ti' \t-hi; • . (n-t;i-n' DAHLGREN AND KKPHIR, 1908, Text-Book of Principles of Animal Histology, p. 88, fi • ' NUvin.

1908, Papers, from tin-- 'I'oriur. i l..il«»at<>i\ of the Carnegie In 'itntnui ot Wa-.liini;ton Puhln ,nion. \... 102. p. 1 1 -, (the cause of rhytlinti! .il pnl .111011 ); Popular Scinui- Monthh. Mil. 7;, pp. 4X1 4X-, 4 hi;1.; 1909, Rrport of ?th Interna- tiona! Xooloi;ii.al (.'ont^n-'s, 4 |>p. — Harvey 1909, Year Book of the Carnepie Institution ot Washington] No. S, p. 119.

Cassiopea frondosa, FKWKV-. 1^X2, Hull. Museum Comp. Zool. at Harvard College, vol. 9, p. 254, plate I, figs. 7-19; plate 2, figs, i, 2; plate 3, figs. 1-3, 9, ioj Ibid., 1883, p. So, plate i, fig. 16.

The disk is usually about 150 mm. in diameter, although Bigelow records one from Jamaica 240 mm. wide. It is flat and with rounded edges. There is a well-marked con- cavity at the middle of the exumbrella, the diameter of which is about equal to the disk- radius. It enables the medusa to cling firmly to any smooth surface as by a sucker.

The number of the marginal sense-organs ranges from 1 1 to 23, although there are usu.ilh about 16. For example, in 25 medusa taken at random and ranging in si/.e trom 23 to 149 mm., one had 13 marginal sense-organs, i had 14, i bad 15, 12 had 16. 5 had 17, i had 18, 1 had 19, 2 had 2O. I have seen one medusa with 1 1 and one with 23 sense-organs. The number is independent of the si/.e of medusa, being determined at time of strobih/.ation.

The sense-organs are short, blunt, and club-shaped, and are set within niches protected above by a shelf-like membrane spanning the cleft between the adjacent lappets. There is no exumbrella pit above the club. Kach sense-organ contains a terminal mass of entodermal crystals and an aboral cup-shaped cctodermal ocellus having reddish-brown pigment. I here are 5 short, blunt, rounded lappets between each successive pair <>t st us. .ugans; the 2 lappets adjacent to the sense-organs are only about half as wide as the others. The mouth-arm disk, which projects as a flat plate from the center of the subumbrella, is only about two-thirds as wide as the disk-radius. 4 pairs of adradial mouth-arms arise from this disk. Each of these 8 mouth-arms is about 1.25 times as long as radius of bell and projects somewhat beyond bell-margin. These mouth-arms are triangular in cross-section, their aboral surface bem» broad and flat; they each give rise to 10 to 15 alternate, primary branches, which in turn give rise to secondary blanches. These branches are commonly longer than in C. fronJosa and are also longer and stouter than in (',. ,in.li',tn,-Ja Eschscholt/. and more slender and have more primary branches than in (.'. polypoi.L* Keller. In the axil of each piimai\ branch ot the mouth-arms is a single, flat, ribbon-like filament, which \aiies in length with the size of the adjacent branch. There are also 5 to 13 large, ribbon-shaped filaments upon the oral surface of the mouth-arm disk. The largest filament is at the center and is fully one-tonnli as lon<; as the bell-diameter. The filaments decrease successively in length out over the mouth-arms; those at the tips of the arms being only about one-seventh as long as those at the center. In addition to the filaments there are numerous short club-shaped, nematocyst- bearing vesicles scattered among the mouths.

The mouths are found upon the oial (uppermost as the medusa lies upon the bottom) sides of the primary and secondary branches of the mouth-arms, and to some extent upon the oral sides of the 8 basal trunks of the arms. There are no mouths at the center ol the

642

MEDUSAE OF THK WORLD.

FIG. 402. — Cassiopea xamachana, after R. P. Bigelow, in Mem. Boston Soc. Natural History.

bj bud growing from side of scyphostoma; cd, circum-oral disk or peristome; t7, interrhopalial lobe; tt, interrhopalial tentacle; m, mouth; p, proboscis; r/;/, rhopalial tentacle; /, tentacle.

25, strobila, in which the degeneration of the rhopalial tentacles is nearly complete and the interrhopalial tentacles have begun to degenerate. 26, a complete strobila. The basal polyp bears a bud which broke of! and swam away while the drawing was being made. The ephyrula was detached during the following night. The rhopalia are visible through the umbrella. At y is a pair of twin rhopalia (compare Vj fig- 30). 27, basal polyp of same specimen, a few hours after separation of the ephyrula. 28, optical section of same. 29, an ephyrula recently set free; oral aspect, gastric filaments visible through mouth; X 31. 30, specimen of about same age, showing variations of margin at u, w, y and 2; X 31.

RHIZOSTOM.K (' \>S|M1'KA. <t 1.'!

mouth-arm disk in the full-grown medusa, although they are commonly found near the edges of the disk. The mouths are (ringed with a multitude ot fine, waving tentacles.

There are 4 small, deep, oval-shaped, interradial subgenital pits, and 4 separate m- vaginated genital sacs. Central stomach is cruciform, being encroached upon at the inter- ladial sides by the 4 sac-like gonads. 1 he axial ducts of the 8 mouth-arms empty into this central stomach at the 4 principal radii. The central stomach also gives rise to twice as many radial vessels in the subumbrella as there are marginal sense-organs. Every alternate vessel extends to a sense-organ, the others going to intermediate parts ot the nm. All of these radial vessels are put into communication one with the other by numerous anastomosing branches; but there is no well-defined circular vessel such as is figured by Haeckel in Cassiopea ornntn.

There is a well-developed zone ot circular muscle-fibers in the outer halt-radius of the subumbrella. These have a more and more cuspate trend as we near the center ot the disk, there being twice as many cusps as there are radial vessels, the outward convexities of the cusps being between the vessels.

The general color of the medusa is greenish-gray-blue, the greenish color being due to clusters of commensal plant-cells within the gelatinous substance of the disk near the surface. It the medusa be maintained in darkness for a month this green color disappears, leaving the animal a pale, translucent blue-gray. Around the outer edge of the central concavity of the exumbrella is a wide, dull white circle, edged on its inner side with faint gray-brown. A more or less Y-shaped, radial, white stripe extends outward from the broad ring in the radii of the sense-organs, the sense-organ being in the center of the crotch of the Y. In addition a single, radial stripe extends outward down the middle of the exumbrella side of each marginal lappet. Occasionally these radial stripes are more or less separated from the broad, white circle. Conspicuous spoke-like, white stripes extend outward in the radii of the sense-organs. These are white regions found in the gelatinous substance of the bell and extend half-way through the gelatinous substance from the subumbrella toward the exumbrella surface. The mouths, filaments, and vesicles are olive or olive-brown, the vesicles and filaments being of a decided green. Among the many color varieties there is a rare one in which the spoke-like, dull white spots are diamond-shaped, and there is no broad, white ring on the exumbrella. The whole medusa is more translucent than are the more abundant medusae with the white ring. They are also smaller than the common form. Curiously enough this color variety bears a striking resemblance to Cassiopea ndrosia Agassiz and Mayer, from the Fiji Islands, South Pacific. Various forms of its color patterns are shown in the photographs in plates 70 to 72 taken from lite by the author.

I find that Cassiopca can thrive well in darkness for more than a month, hence the medusa is not dependent upon its commensal plant cells for the oxygen it requires. In this connection \\hitnev, 1907 (Biol. Bulletin, vol. 13, No. 6, p. 291), finds that if green li\Jra be placed temporarily in a 0.5 to 1.5 per cent solution of glycerin, the green algae (Chlorella vulgaris) pass out through the mouth. Then if the h\Jra be replaced in w:ater it will grow nor- mally, but remains clear and does not regain the green bodies even when placed in an aquar- ium with algx.

This medusa was discovered in great abundance by Dr. R. P. Bigelow in a salt-water lagoon called the Great Salt Pond, near Port Henderson, Kingston Harbor, Jamaica. It is also exceedingly common in the salt-water moat of Fort Jefferson, Tortugas, Florida, where it is found upon the weedv bottom throughout the summer; and it occurs in many semi-stagnant, salt lagoons along the Florida Reef as far north as Miami.

The early stages of the development of the egg into the scyphostoma are as yet unob- served, but the process of the formation of asexual buds by the scyphostoma has been elabor- ately studied by Bigelow and observed also by Perkins. The buds arise from the perradial sides of the calyx of the scyphostoma near the point of origin of the stem. Scyphostomae are never found with more than two buds attached. When two are present the older is always attached to the apex of the younger bud. The bud is at first hemispherical, hernia-like; then elongated, and finally spindle-shaped. The ectoderm, entodcrm, and mesogloea of the bud are produced from the corresponding layers of the parent scyphostoma, and the 4 ectodermal, septal muscles of the bud are derived from out-growths of one or both of the septal muscles of the parent which lie in the interradii adjoining the perradial area of hud formation. The

644

MEDUS,E OF THE WOULD.

hud is set free as a spindle-shaped larva which swims by means of cilia. After 2 or 3 days the mouth breaks through at the pole which was at the proximal end of the bud while it was attached to the parent, thus resembling the case of budding in Cotylorhiza. The mouth is not formed by an invagination ot the ectoderm, but breaks through by the local disappear- ance of the mesoglcea and the fusion of ectoderm and entoderm at the posterior end of the larva. The anterior end then elongates to form the stem of attachment, and in about 4 or 5 days after being set free the larva fastens itself to some solid object.

23

FIG. 403. — Cassiopea xamachana, after R. P. Bigelow, in Mem. Boston Soc. Natural History.

//, interrhopalial tentacle; oc, ocellus; rht, rhopalial tentacle; .v, abnormal branched tentacle.

17, scyphostoma showing first traces of rhopalial structure. 18, small part of margin, more highly magni- fied. 19, scyphostoma at slightly older stage. 20, small part of margin of similar larva, zi, early stage in stabilization. 22, rhopalial tentacle of same specimen seen from side. 23, older rhopalial tentacle. 24, strobila in which rhopalial tentacles have begun to degenerate.

KHIZOSTOM/E — CASSIOPEA. 645

Usually the 4 perradial tentacles are soon supplemented by the 4 interradial ones, and in about 3 days after they first appear the 8 tentacles are as long as the proboscis of the scypho- stonia. 8 adradial tentacles then develop. The number and arrangement ot the tentacles is, however, very variable but finally there are about 32. In any case there are twice as many tentacles as there are to be rhopalia. The full-grown tentacles are tapering, slender, and about 3 times as long as the body of the scyphostoma. Half of them are erect, and the alternate half stretch more horizontally outward.

The 4 primary, gastric pouches are not formed by evagination from ectoderm and ento- derm alternately, as in the sexually produced scyphostoma of Aurellia, etc. .according to Goette, but are wholly entodermal as Had/.i finds them to be in Chrysaora, and simply separated one from another by the ingrowth of the 4 interradial septa. At first the septa are simple, entire buttresses of entoderm with an axial sheet of mesogloea, but later each septum becomes peilor- ated immediately under the interradial tentacles, thus forming a ring-sinus. There are 4 longi- tudinal strands of septal muscles, I in the mesogloea of each septum.

The septa bear no definite relation to the exact position of the interradial tentacles, for these may arise on either side of or in the plane of a septum. In this respect the scypho- stomse resemble those of Aurtllia and Cotylorhiza according to Claus, and differ from the .Jnthozoa, in which the tentacles are invariably interseptal. Every alternate tentacle stands erect while the others extend outwardly. When the scyphostoma disk is about 2 mm. wide, conical enlargements which contain crystalline concretions are observed in the entoderm at the bases of the erect tentacles. An ectodermal ocellus develops upon the aboral (lower) side of each conical enlargement and the tentacle itself begins to degenerate, becoming finally absorbed, leaving only the sense-club with its ectodermal ocellus and terminal mass ot cnto- dermal concretions. When the tentacles begin to degenerate, slight pulsating movements ot the disk commence. The marginal lobes grow out while the rhopalia are being formed, and finally the interrhopalial tentacles are also absorbed.

Strobilization is monodiscus, but the scyphostoma after setting free the ephyra develops new tentacles and gastric pouches, and may strobilate a second time.

The young ephyra has the same number of marginal sense-organs as the adult medusa. It has 4 simple lips and a central mouth-opening. Then the angles of the lips become extended to form 8 oral arms, very much as in the adult Aurosa. Then there is a stage wherein the oesophagus is disided into 4 tubes with 3 osculz and an oral vesicle on each arm. Rhisostoma and Cotylorhiza go through a similar stage. The septal muscles and their funnel-cavities disappear wholly in the ephyra, as do also the 4 interradial septa.

Mayer, 1906, 1907, 1908, finds that the stimulus which produces pulsation in Cassiopca is nervous in nature and will pass over newly regenerated tissue which contains nervous, but no muscular elements. Moreover, if the muscles be paralyzed by magnesium the pulsation- stimulus still travels through tin- nervous network of the subumbrelia, even though the muscles can not respond to its presence by contraction.

If an annulus, or strip of any shape constituting a closed circuit, be cut from the- suh- umbrella and stimulated momentarily at any one point, 2 waves of contraction start in opposite directions around the strip from this stimulated point. By pressing upon one side ot the ring we dampen and reduce the strength of the initial wave passing over that side, and when ili< two waxes meet the stronger wave overpowers and annuls the weak one. I bus a single contraction-wave is entrapped in the ring-circuit and travels constantly around it at a uni- form rate. The mechanical arrangement of the pulsating medusa in nature is such as to prevent the formation of such continuous pulsation-waves — the pulsations are recurrent and each contraction-wave is annulled as soon as it has produced a single contraction ot the medusa.

The sea-water is a balanced rluid for the medusa, neither stimulating nor inhibiting its pulsations. This balance is due to the fact that the ionic soJiunt of sea-water is a powerful nervous and muscular stimulant, but the tiitigiirsiuin, cnli'iitni, and f>r>tii>Minn are inhibitors and annul the stimulus produced by the sodium. If calcium be absent the mugih-Muin <]uickly checks all pulsation. On the other hand, a slight increase in the ^Jiiim seises as a nelsons stimulus which overcomes the inhibiting tendency of the m<i«ti,-*iuni, calcium, and /i and produces contraction.

646 MEDUS.E OF THE WORLD.

The pulsation-stimulus is engendered in the marginal sense-organs. A uric oxalate of sodium is developed constantly in the entodermal cells of the outer end of each sense-club. This oxalate precipitates calcium, thus forming the crystalline concretions which consist of calcium uric oxalate, and at the same time it sets free such soluble stimulants as NaCl and Na,Sor Thus we find that the sense-clubs are engaged in the maintenance of a slight con- centration of sodium over and above that found in the sea-water itself. This slight excess of the sodium ion is a stimulant to the nervous elements within the sense-club and the nervous elements respond to it recurrently, producing the rhythmical contractions of the muscles.

If a disk without marginal sense-organs be set into pulsation and then disturbed by a sudden current in the sea-water, etc., it displays excitement by markedly increasing the amplitude of its pulsations. Hence its ability to display excitement is not dependent upon the sense-organs, but upon the general nervous tissues of the subumbrella.

When the marginal sense-organs regenerate, each one appears with a short, hernia-like side branch, which disappears later. In this connection it is interesting to see that the sense- organs are normally formed as side buds from the bases of each alternate tentacle of the scyphostoma, and then the tentacles themselves are absorbed. Thus when they regenerate they display a tendency to replace the tentacle as well as the sense-club.

In 1909 I succeeded in grafting two individuals of C. xamachana, side by side, so that their subumbrellas joined. The double-medusa then pulsated constantly at the rate of the faster individual which initiated and controlled all of the rhythmical movements; but if one pinched the controlled medusa its rate increased and it then assumed a temporary control of the double animal. Hence the complex always pulsated at the rate of its fastest member. Hargitt attained a similar result with 2 individuals of Gonionernus murbachii, but in this case the rims were attached around nearly their entire edges so that any movement of one medusa must necessarily cause a corresponding movement of the other. In the two Cassiopeas, however, the contact was at a single narrow bridge of tissue only, and indeed the medusas pul- sated independently until the nerve-nets of their subumbrellas joined in the process of regeneration.

The color of the umbrella of C. xamachana is mainly due to the presence of numerous symbiotic algae, Tjooxanthella, which Bigelow finds contain starch, cellulose, and chlorophvl. These plant cells are globular and occur in small clusters imbedded in the mesogloea and are greenish-brown in color.

A well-marked, conical, pit-like depression is occasionally seen upon the aboral side of each mouth-arm near its point of origin from the arm-disk, but more commonly in male than in female medusas. The female medusae greatly outnumber the males. Perkins believes that the medusae may be hermaphroditic, but of this we have no evidence. Pseudorhiza haeckelii is, however, known to be hermaphroditic, the spermaries being in the gutters of the mouth- arms.

Zeleny, 1907, finds that medusae maintained in pulsation appear to regenerate at about the same rate as if the disk were at rest. Certainly the functional activity of pulsation seems to be of no aid in accelerating regeneration, for Stockard also finds that the medusa regenerates at practically the same rate whether it be pulsating or at rest.

Stockard, 1907, discovered that tissues removed from various parts of the subumbrella regenerate more rapidly the nearer they are to the disk-center, and less rapidly as the periph- ery is approached, thus according with the rule discovered by Morgan in the regenerating fish's fin — the deeper the level of the cut the more rapid the regeneration.

In 1908, Stockard made the interesting discovery that if the medusae be starved while they regenerate lost arms the disk of the medusa shrinks during the process of regeneration, and its rate of decrease is greater the greater the number of removed arms. The regenerating tissue evidently possesses a greater capacity lor absorbing nutriment than does the somatic tissue of the disk itself, and in this respect the regenerating tissue behaves as does that of cancer which grows rapidly even when the normal tissues surrounding it are wasting away. (See Year Book of the Carnegie Institution of Washington, No. 7, p. 131, 1908.)

PLATE 72.

The three uppermost figures are of Cassiopea froniiosa and show two varieties of color pattern ot the exumbrella and one view of the subumbrella showing the mouth-arms.

O

The seven lower figures are of Cassiopea xamachana showing varieties in color-pattern. The central figure shows the exumbrella of a medusa with its mouth-arms spreading outward.

Photographed from lite, by the author. The medusae are seen upon a

sandy bottom.

— CASSIOPEA. Ill,

Cassiopea frondosa Lamarck. Plate 69, figs, i to 3; plate 72, the 3 upper figures.

Medusa frondosa, PALLAS, 1774, Spicilcgia Zodi i . 10, pp. 29, 30, plate 2, figs. i-;. CMIMN. i-sv ir-r,

tomus I, pars 6, p. 3157.— Bosr, 1802, Hist. N.K. J Vers., tome 2, p. 170.

Cassiopea frondosa, LAMAKCK, 1816, Hist. N.il. Arum, -ans \Yrt., tome 2, p. 51;. I !.rn,

p. 43. — TlLE8!US| 1834, Acad ' ! . 'a., torn. 15, pp. 263, 278, tab. • l.> •. . : •

Acal., p. 405. — MiLNE-EDWARDS, 1849, Cuvirr's Rrgne Animal, Zooph., plate 51, fu'. ',. I'IUKI-.-. mci>. V .ir I Carnegie Institution of Washington, No. 4, p. 115; MJOX. Publication No. 102, < u I 152,

plate 4.

Cassiopea pa/lasii, P£RON ct Lcsueur, 1808, Anna], der Mus. Hist. Nat., Paris, tome 14. p. -,;-. \r. 85.

Polyclonia frondosa, ACASSIZ, L., 1860, Cont. Nat. Hist. U. S., vol. 3, plates 13, 130; 1862, IbiJ., vol. 4, pp. 139-148, 159. — AGASSIZ, A., 1865, North Amer. Acal., p. 41 ; rXSr, Vitun . \ol. 24, p. 509. See aim Archer, H., Il/iJ., p. 307. - HMI >.> r. 1880, Syst.,1. i Mr in .-n, p. 568; 1 88 1, Report H..M.S. C/iallr n g, •, . Zool.,1 i. 4. p. XMII. VAMI..I i >s. iXSX. HiMiotheu Zoologica, B.I. r, Heft. 3, p. 40. — Bic;r.io\v, R. P., 1893, Johns Hopkins I n ' < 'Mars. vol. 2. No. 106, p. 10*. (habits,

physiology).— PERKINS, 1906, Year Book, Carnegie Institution of Washington, No. 4, p. 115; i.,o,X, Publication No. 102, t'arncgie Institution of Washington, p. 152.

Disk flat, with rounded edge, and about 120 to 260 mm. in diameter. I lu-ic is no con- cavity at the center ot the exumbrella, such as is seen in Cassiopea tcamachana. 1 "here are constantly 12 marginal sense-organs in ('.. jronJosti, 4 perradial, 8 acliadia]. iai.li nt" which contains a terminal entodermal mass of crystalline concretions. Thi-ie au no ocelli. There are 60 short, subrectangular, nearly straight-edged, marginal lap]>ets. 5 lni\\ecn i-ai h sur- cessive pair ot marginal s< nsr-oio-ms. The lappets flanking the sense-oi«;aiis .nt only hall as wide as the other lappets. The 4 pairs of mouth-arms anse t'n>ni a shallow, flat, niouth- arm-disk at the center ot' the subumbrella; this arm-disk is not quite as wide as the semi- diameter of the medusa. The mouth -a mis, which are about three-fourths as longas bell-radius, usually bifurcate at their tree ends and <M\e rise to short, piiinatt- side blanches tiom then oral sides; but occasionally the branches are quite long as in (.',itM'-/>,-,i \,nn,i, h,iiin. The numerous trilled mouths are found exclu.si\el\ upon their lo\\ei sidis, the tippei sides ot the mouth-arms being smooth and without mouths. Scattered <|mu u ni I or ml \ between the mouths are 30 to 40 small, expanded, flat, leaf-shaped vesicles. Tin n are 4 small, nnmd, inteiradial, subgenital pits, and 4 separate, in vagina ted genital sacs which project into the stomach- 1 avity. A duct extends from each of the 8 mouth-arms into the central stomach, and 24 radial-canals pass outward from the stomach into the subumbrella and are put mi<> coinmiimi-.iuon one with another by a network of anastomosing vessels. 12 radial-canals go to ilie marginal sense-organs and 12 are intermediate in position.

General color of gelatinous substance amber-yellow, slight h oh\e, 01 giecmsh. Just above each of the 12 marginal sense-organs is usually a single, large, bilatiial. bean-shaped white spot in the gelatinous substance of the exumbrella. Thcic is also a smallei \\lnie spot in each marginal lappet, and above this an irregular line of .j to 5 smaller whin spo.s between each successive pair of marginal sense-organs. A more or less broken, axial, w hue line extends through the length of each mouth-arm in the gelatinous substance. The fulled mouths aie of a cinnamon color and the leaf-like vesicles are opaque, dull \\hite. 'I he spots upon the bell are very variable in number and arrangement i see plates 'u, and 72).

Ctissiofifa fronJoiii is found throughout tJie West Indian region and the Flojula R. • Perkins observes that it lives upon saiulv rather than \ucd\ bottoms. In common with oihei species of the genus it lies upon the bottom w ii h the oral suit'ace and mouth-arms uppemiost. In this position it lemains for long intervals of time, slowK contiacting its disk in a sluggish rhythm. This movement serves not onh to maintain the disk upon the bottom, but to > reat< a water-current overthe mouth-arms. It prefers purer water than ('. xamacfiana, and is usualh found in protected places among the mangroves in the cuts between the Florida Kr\s.

In Kingston Harbor, [amaica, this medusa is found upon the muddj bottoms ot protected lagoons, especially in those simoundcd by mangroves, neat the h.uboi enuance where the water is quite pure. In Jamaica it attains to a fa i greater size than in Florida. \specimeii which I found in a mangnne lagoon near I 'oil Roxal in Match, n^")- «as ot the following dimensions in mm.: Hell 251; \\ide, aim-disk 05 wide, mouth-arms 121) long, pinnateh and complexlv bianchcil. and projecting be\ond the rim of the bell. C'oloi as in the Honda specimens. I am told that the medusa becomes even l.ugcr in Jain

I,. Agassi/ ( 1X02, p. 1471 showed that the young eplu la of this sjiecies poss. ss. s a ceniial mouth-opening which disappears in the adult.

648 MEDUSA OF THE WORLD.

C. fronJosa can at once be distinguished from C. xamackana by its amber color, the absence of ocelli on its rhopalia, the absence of a sucker-like concavity upon its exumbrella, and by the^fact that it has constantly 12 marginal sense-organs, whereas C. xamachana has II to 23 (see plate 69). It is far less hardy in aquaria than C. xamachana.

According to Bigelow, 1893, in the adult female the mouths disappear from the oral disk while at the same time the oral vesicles increase in number until they are closely crowded together and completely cover it. The eggs are discharged from the ovaries into the stomach, where cleavage begins; they then pass out on to the oral disk and are to be found there in large numbers, cemented together in small, reticulated clusters at the bases of the vesicles; they remain there until some time after they have become ciliated planulae. Bigelow reared the scyphostomae of this species to the 8-tentacle stage. The young scyphostoma appears to be entirely similar to those of other species of Cassiopea.

Dr. R. P. Bigelow has shown that while the vesicles on the oral surface of the disk serve to protect the young, those of the mouth-arms serve to capture food. These vesicles usually stand upright, but upon being struck by an unwary copepod they bend down and close the mouth of the nearest funnel in the manner of a lid. The prey thus finds itself within one of the mouths, tightly shut in by the overlying vesicle.

Cassiopea ornata Haeckel.

Cassiopea ornata, HAECKEL, 1880, Syst. der Medusen, p. 570, taf. 37, fign. 1-8. — HAMANN, 1881, Jena. Zeit.fiir Naturw.,Bd. 15, p. 248 (structure of the mouth-arms).

Bell 100 to 120 mm. wide, 30 to 40 mm. high, flat and shield-shaped. 16 rhopalia, 80 lappets, 96 white spots, as in C. andromeda. Mouth-arms cylindrical, slender, and somewhat longer than bell-radius, not broad and flat as in the typical C. andromeda. There are only small, club-shaped vesicles between the mouths. The characteristic feature of this species is said to be the presence of 2 distinct ring-canals. The inner ring-canal connects the 16 principal radial-canals at an annulus some distance inward from the margin, while the outer ring- canal is at the margin. The 16 inter-rhopalar radial-canals are narrower than the rhopalar, and soon lose themselves in the network of anastomosing vessels of the subumbrella, whereas the 16 rhopalar canals extend straight out to the sense-organs. The network of vessels becomes fine-meshed on the inner side of the ring-canal, but on its outer side it gives off a wide-meshed network, the meshes of which become finer as they near the bell-margin, where there is a marginal ring-canal. These hypothetical ring-canals are so peculiar and unlike the simple net- work seen in other species of Cassiopea that the fact of their existence requires confirmation. Haeckel alone has observed them. The medusa is from the Pelew Islands and New Guinea.

I find among the collections of the U. S. Fisheries Bureau steamer Albatross seven speci- mens of a medusa which appears to be a closely related variety of, if not identical with, C. ornata. None of these has the remarkable ring-canals figured by Haeckel, and this leads me to doubt their existence in Haeckel's medusa. The dimensions in mm. of the largest of these medusae are as follows: Bell 76 wide; exumbrella flat, smooth and without an aboral sucker- cavity; arm-disk 39 wide; mouth-arms 31 long, stout and flattened laterally, with 9 to 12 short, stout, blunt, dentritically arranged side branches. A few very small, flat, club-like appendages less than I mm. long scattered among the mouths of the mouth-arms; but these become larger near the arm-disk. The arm-disk itself is thickly covered with irregularly shaped tuber-like, or truffle-shaped, appendages, the largest being 3 to 4 mm. long. There are 16 rhopalia. 5X16 blunt, square-edged, marginal lappets. 32 tree-like radial-canals which give off an anasto- mosing network, but no distinctly differentiated ring-canal. These medusae were obtained in the following localities in the Philippine Islands in 1908: 3 large specimens from near shore at Tataan, Simaluc Islands, February 19 and 20; 3 from Subic Bay, January 7, in a seine, and I from Catbalogan, Samar, on April 16.

Cassiopea ornata var. digitata Maas. Cassiopea ornata var. digitata, MAAS, 1093, Scyphomedusen der Siboga Expedition, Monog. 11, pp. 40, 45, taf. 4, fign. 26, 30.

Bell about 100 mm. wide, very flat, without an aboral concavity or a dome. 16 marginal sense-organs, 32 rhopalar and 3X i6,or more, velar lappets which are, however, quite irregularly

RHIZOSTOM/E — CASSK >I>K A . 649

arranged. 16 long, violet-colored, radial stripes upon the subumbrella. The mouth-arms branch in a hand-shaped manner, the terminal branches lesemhling fingers in shape. These mouth-arms are 1.5 times as long as the disk-radius. There are no large club-shaped appen- dages between the mouths, all being very small. The mouths are brown to \ inlet.

This variety is distinguished from the typical (',. unxitii by its color and by its finoi-r- shaped mouth-arms. It is found among the islands of the Malay Archipelago, at Saleyer, and elsewhere.

Cassiopea depressa Haeckel.

Cassiopea depressa, HAECKFL, 1880, Syst. di-r Mrdusrn, p. 572.

Bell flat, shield-shaped, 100 to 120 mm. wide, l 5 to 20 mm. high. Exumbrella smooth, without aboral concavity or dome. id rhopalia, 144 wide, pointed, but not prominent lappets. In each paramere 7 velar between 2 ocular lappets. 8 very wide, flat mouth-arms shorter than the bell-radius and with 6 to 8 short, wide-spreading main-branches. Numerous very small club-shaped vesicles between the mouths, hardly larger than the rhopalia, onh 0.4 to 0.8 mm. long. No radial spots on the exumbrella.

Found at Madagascar ami at the fjuerimba Islands off Mosambique, East Africa. Described in detail by Haeckel.

43-

Cassiopea depressa var. picta Vanhoffen.

Cassiopeia picta, VANHOFFEN, 1888, Bibliotheca Zoolu^ka, BJ. i, Hflt. 3, p. 26, taf. 2, fi^n. i, 2. Cassiopea depressa, var. picta, MAAS, 1903, Scyphonu'dusfn der Siboga Expedition, Monog. n, p.

Disk flat, 60 to 85 mm. wide. 14 ( :) to 16 marginal sense-organs. 112 (7X16) velar and 32 ocular lappets, all similar each to each, and blunt and small. The lappets are irregu- larly developed in the two specimens described by Vanhoffen, and while there are usually 5 velar lappets between each successive pair of ocular lappets, in some parameres there are o, 3, 8, or even 10 velar lappets. Arm-disk octagonal with 8 equal sides and half as wide as bell-diameter. The free, projecting parts of the 8 mouth-arms are somewhat shorter than the radius of the disk and project about one-third of their length beyond the bell-margin. These mouth-arms are pinnately branched with short branches as in C. \uniiii liiin,i, and have no appendages excepting small lancet-shaped ones, as in G. tulrosia and C. Jcpressa. The musculature is similar to that of C. ornnta. The 32 radial-canals give off anastomosing side branches which place them all in connection one with another. There are no distinctly differentiated ring-canals.

Ground color of disk translucent opal. There are 16 large white spots over the 1 6 marginal sense-organs, and in the large medusa these are fused into a ring of varying width, bein<; widest in the radii of the sense-organs and narrowest in intermediate positions. Peripheral to this white ring are 144 white, linear-oval streaks, one oxer each lappet; those over the 32 ocular lappets smallest, those over the interocular lappets the longest. The }> small spots over the ocular lappets are fused with the lli large, white, radial spots, id while rays in the subumbrella appear as large egg-shaped spots, their blunt ends inwards. They are in the radii of the sense-organs and extend from the outer edges ot the central stomach and gonads outwards with their radial edges almost touching.

This species was described by Vanhoffen tiom two specimens found near Heibul in the Red Sea, in December, 1884. It differs from other species of Cassiopea in the large number of its marginal lappets and its very wide arm-disk. There is no raised central sucker on the exumbrella and no large club-shaped vesicles on the mouth-arms, such as are seen in (.'. pol\>f>oidcs.

Cassiopea mertensii Brandt.

Cassiopea mcrtensii, BRANDT, 1838, Mrin. Acad. Sci. Si. IVtn • l.om u., s, i. N'.n., scr. 6, tome 4, p. 396, taf. 20-23.- "*" K>l •

1880, Syst. der Meduscn, p. 572. Cassiopeja mertensii, MAAS, 1903, Scyphomediisen drr Siboga Eipr.l., \|..n.ir. u, p. 40.

Bell evenly rounded without an aboral concavity, 100 to 120 mm. wide, 30 to 40 mm. high. 16 rhopalia. 128 small, tongue-shaped, prominently projecting lappets. In each paramere 6 velar between 2 ocular lappets. 8 cylindrical mouth-arms 1.5 times as long a

650

MEDUS.'E OF THE WORLD.

bell-radius give off 8 to 12 main branches each, which also branch in a tree-like manner. Numerous large club-shaped vesicles between the mouths, some half as long as bell-radius.

Bell yellowish, rusty-brown, lighter in the center. Radial streaks reddish-brown. There are 2 white, half-moon-shaped spots over each rhopahum. Upper surfaces of mouth-arms light-yellow. Mouths dark rusty-yellow. Vesicles white.

Found at Ualan, Caroline Islands, tropical Pacific.

Cassiopea ndrosia Agassiz and Mayer.

Cassiopea ndrosia, AGASSIZ AND MAYER, 1899, Bull. Museum Comp. Zool. at Harvard College, vol. 32, p. 175, plate 14, figs.

45, 46. Cassiopeja rnertensii var. ndrosia, MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. II, pp. 40, 43.

Bell 50 mm. in diameter with a shallow concavity at the center of the exumbrella, similar to that of C. xamachana. Rhopalia variable in number, 18 to 22. Marginal lappets very indistinct but there are 2 velar flanked by 2 ocular lappets in each paramere. Mouth-arms cylindrical, 1.5 times as long as bell-radius, and branched in a tree-like manner. Each arm gives off 6 to 12 main side branches. There are numerous small, flattened, expanded leaf- shaped vesicles between the mouths, most numerous at center of arm-disk. No ribbon- shaped filaments. 4 small, round, subgenital ostia. 4 separate genital sacs.

General color of bell grayish-brown, with bluish, inter-rhopalar, radiating streaks and white radiations in the subumbrella in the rhopalar radii. A large, spearhead-shaped white spot with its pointed end outward is found near the margin of the exumbrella above each sense-organ; there are also 4 small, radially elongated, white spots near the margin in each paramere — one above each of the rudimentary lappets. The aboral surfaces of the mouth- arms are grayish-white, the mouths deep brown, and the vesicles olive-green.

Found upon muddy bottoms in Suva Harbor and at Komo Island, Fiji Islands, South Pacific, in November.

C. ndrosia lacks the large vesicles of C. mertensn and has an aboral exumbrella concavity, whereas the bell of C. mertensn is, apparently, evenly rounded. It is most closely related to C. xamachana of the West Indies, and resembles one of its color varieties, but lacks the ribbon- like filaments of C. xamachana.

RHIZOSTOMATA DICHOTOMA Vanhoffen 1888.

Rhizoslomata dicliotoma, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 39. — MAAS, 1903, Scyphomedusen der

Siboga Expedition., Monog. 1 1, p. 31 . Chaunostomid*s + Cepheidte, CLAUS, 1883, Organisation und Entwick. Medusen, Leipzig. — VON LENDENFELD, 1888, Zeit. fur

wissen. Zool., Bd. 47, p. 211. Radiomyaria, MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. 1 1, p. 89; 1907, Ergeb. und Fort. Zool., Bd. i, p. 201.

CHARACTERS OF THE GROUP.

8 separate mouth-arms the lower ends of each one of which gives rise to 2 expanded, leaf-like side-walls, or lateral membranes, the outer edges of which give rise to secondary branches and bear the frilled mouths. Thus each arm is V-shaped in cross-section (fig. 404).

.. 404. — Diagrammatic representation of the shape and position of the mouth-arms in the Rhhtostomata dtchotoma. The figure on the right hand shows a section of one of the mouth-arms. The middle figure is an oral view of the bell.

Hill/.' IST< iM.K — CKPHKA. 651

There are no scapulets upon tin- mouth-arms. The radial-muscles are powerfully and the ring muscles weakly developed. A description ot rlu- genera follows:

(.> l>lii-<i PKKON AM> List M K, iSou. Exumbrella with a central area bearing wart-shaped projections.

I'.ut \lmln ,i I.. \' • i/, 1862. Exumbrella with a smooth central dome without wart-like elevations. Radial-canals

of tin- 1«-11 ;ill similar each to each. Polyrliiza L. AGASSI/-, 1862. Exumbrella with a central concavity and with radiating furrows.

Genus CEPHEA Pe>on and Lesueur, 1809.

Cefhra, I'tRu.N > i l.tM-t.uR, 1809, Annal du Mus. Hist. Nat., tome 14, p. 360.— ESCHSCHOLTZ, 1829, Sys,t. dc-r Acalcphcn, p. 55. — I.ISSON, 1843, Hist. Zooph. Ai-al., p. 410. — AGASSIZ, 1862, Cont. Nat. Hist. U. S., vol. 4, p. 155.— -H*i< kM. 1880, Svit. der Medusen, p. ^73. --VAMIOH i N, 1888, Bibliotheca Zoologica, Heft. 3, p. 39; 1902, \Visscn. Ergcb. dcutsch. Tiefsee ExpeJ. I'aldhia, BJ. 3, Lfg. i, p. 45.

Ccf>hca+ Netrostoma, MAAS, 1905, Scypliomedusen der Siboga Expect., Monog. 1 1, pp. 31, 32, 35, 81, 89.

\etrosloma, SCHUI.TZE, L. S., 1898, Denkschr. Med. Nat. Gesell. Jena., Bd. 8, p. 4^7.

Micrtstylus+Ptrirhixa, KIMIINIII-VK, 1902, Journal College Sci. Tokyo, Japan, vol. 17, Art. 7, pp. 11, 13.

Xtvlorlih,!, HAM k'H,, 1880, Syst. der Mcilus,en, p. 6l2.

Halipetasus, SCHULTZK, 1898, Uenksclir. Med. N.it. Gesell. Jena, Bd. 8, p. 458.

The oldest known species is "Medusa octost\ln" of Forskal. and this may serve as the i \ pi- ot tin- genus Cephea.

GENERIC CHARACTERS.

Rliizrist'initita Jiehit'jtiin in which the 8 mouth-arms tork once dichotomously and each fork gives rise to short dichotomous or dendritic branches. Solid, wart-shaped tubercles at the center of the exumbrella. The central stomach gives rise to 8 rhopalar and numerous inter-rhopalai radial-canals, all of which connect with a network of anastomosing vessels in a wide zone near the margin. Rhopalia without ocelli and without exumbrella, sensory pits. There is no definite ring-canal. Development unknown.

The described species of <,Y/>//,w are all found in the tropical Indian Ocean and Pacific region. Cephea cephea (Medusa ccplica, Forskal) is apparently widely distributed over the Indo-Pacific region and is distinguished by its numerous, long, tapering, conical, pointed filaments; its deep rhopalar clefts in the bell-margin; oval velar lappets fused one to another by a thin web, and its brown coloration. C. octostyla of the Red Sea — Malay Archipelago — is distinguished by its very low exumbrella dome with very small tubercles. The marginal lappets are indistinct. Also in C. conifera, C. Jumokuroa, and C. ccerulca the lappets are so indistinct that the bell-margin is entire, save for the deep niches of the 8 rhopalia. In C. Jumo- kuroa and C. ccerulescens the central dome bears warts only on its sides, leaving its apex bare. C. ccerulea has only 16 long filaments, whereas C. conifera has more than 100 and C. dumo- kuron none. In Cephea ccerulescens we find very small tubular and somewhat large spindle- shaped filaments between the mouths, and the subgenital porticus is only partially differ- entiated. In some quadrants the primitive genital sacs may have fused and the fused wall broken down to form an opening, so that one may pass a probe into one subgenital ostia and out through another without pcnci rating any tissue, the passage being continuous and actually a part of the outside world. In other quadrants, however, the gonads may be quite separate one from another or merely fused without any break in the area of fusion. In C. corn/era and C. Jumokuroa, on the other hand, the subgenital porticus is unitary and cruciform, whereas in C. ii-tniu-liitina the 4 genital sacs are fused along their inner walls, but the walls remain unbroken. In Cephea t\phl'>J,-nJrnini the filaments are small and spindle-shaped, and con- fined to the arm-disk.

Ir is evident that we have in the Red Sea, Indian Ocean, and western parts of the tropical Pacific a large number of closely related forms of Cephea displaying many local variations. I think there are only 2 well-marked forms and these are but the extremes of an intergrading series: C. octostyla with low dome or flat exumbrella and small warts, and C. cephea with a high dome and large warts.

L. S. Schultz, 1898, proposes a genus Netrostoma to include R/uzostoma Jichotoma with mouth-arms laterally compressed and several times dichotomously branched; no large fila- ments between the mouths on the mouth-arms, although filaments may be found on the mouth-arm-disk.

652 MIODUS.E OF THK WORLD.

As a matter of fact the mouth-arms of all known species of Cephea give rise to secondary dichotomous, or dendritic, branches, and all are laterally compressed. Moreover, we can not separate genera merely upon the relative size ol the mouth-arm-filaments, for confusion is certain to result.

"Microstylus" of Kishinouye is evidently a Cephea closely allied to C. typhlodendrium.

I have therefore broadened the definition of the genus Cc plica to include all Rhizostoniatu Jicliotoma with a wart-bearing central area upon the exumbrella and with 8 forked mouth- arms, the forms of which are themselves still further branched.

In the collection of Cepheas made by the U. S. Fish Commission steamer Albatross in 1908, I find an intergrading series among specimens of Ccphca collected all at the same time on the surface at Jolo, Philippine Islands. In some there is no central dome, the exumbrella being quite flat, and in others there is a low but well defined dome. In some the exumbrella warts are large and mammiform, while in others they are mere granules, often absent over wide areas or leaving the center smooth. The filaments upon the mouth-aims and arm-disk may be absent or long and filiform. Thus among these intergrading individuals (evidently all of one and the same species) some are identical with Forskal's "AlcJusa octostyla," others are similar to Schultze's "Halipetasus scaber."

Cephea octostyla L. Agassiz.

Medusa octostyla, FOKSKAL, 1775, Descrip-Anim. Itin. Orient, p. 106, No. 18, Icon., tab. 29.

Medusa cephea, LINNE, (Gmclin) 1788, Systema Nature, Ed. 13, p. 3158. \on Medusa cephea, Forskal.

Cephea cvclophora, MILNE-EDWARDS, 1849, Cuvier's Regne animal illustre Zooph., planche 51, fig. 4.

Cephea octoslyla, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 156.

Stylorltizti ottostyla, HAKCKEL, 1880, Syst. der Medusen, p. 613.

( .') Stylorlika polystyla, HAECKEL, 1880, Syst. der Medusen, p. 613.

Halipetasus scaber, SCHTLTZE, L. E., 1898, Denkschrift. Med. Nat. GeseH., Jena, Bd. 8, p. 4^8, taf. 33, fign. 5 und 7.

According to Haeckel and Forskal the bell is 300 mm. wide, flatter than a hemisphere. Surface of exumbrella smooth, without a central dome, and without radiating furrows. 8 rhopalia 50 to 60 ( ?) wide, flatly-rounded, marginal lappets. Rhopalar clefts shallow. Arm- disk wider than bell-radius. 4 small subgenital ostia. 8 bifurcated mouth-arms 1.25 times as long as bell-radius; the forks of each arm as long as undivided upper part of arm. 9 l°ng> stout filaments of uniform caliber arise apparently from the arm-disk. These are 1.5 times as long as diameter of bell and end simply, without terminal knobs. In addition to these filaments there are about 12 short, stout, swollen, club-shaped appendages between the mouths on the lower sides of the arms. The color is blue and hyaline. Arabian coast of the Red Sea.

Forskal's description evidently refers to the medusa figured on his plate 29, not that of plate 30 as stated by Niebuhr, who edited the plates of his work in 1776. While Forskll's figure is remarkably good for its period, his description is too brief and vague to be of value. The description given above has therefore been mainly derived from a study of his figure.

Haeckel's " Stylorhiza polystyla" from Singapore is described from a preserved and damaged specimen. It is said to be 100 mm. wide with fla'ly rounded bell and 80 marginal lappets. In each octant are 8 rectangular velar and 2 small oval ocular lappets. 4 subgenital ostia hardly as wide as the columns between them. Mouth-arms nearly twice as long as bell- radius; many times dichotomously branched, with 16 very long tubular appendages and numerous vesicles upon long pedicels. 8 of the long appendages arise from the bases of the arms and 8 from the crotches of the primary forks. This is probably identical with Forskal's medusa.

Many well-preserved specimens of Cephea octostyla were obtained by the U. S. Fisheries Bureau steamer Albatross at Jolo Anchorage, Philippine Islands, tropical Pacific, in February and March, 1908.

The bell of the large specimens is 90 mm. wide, exumbrella flat; rim vertical, 20 mm. high. Neither central dome nor coronal furrow, but there is a zone of numerous, low, wart-like protuberances upon the exumbrella, leaving the center free. This wart-covered zone is about 40 mm. in diameter and 15 mm. wide, leaving a circular area about 10 mm. in diameter free of warts at the center of the exumbrella. Other parts of the exumbrella are smooth. There are 8 rhopalia set within fairly deep niches. These lack ocelli and have no exumbrella sensory pits. There are about 72 indistinct lappets, 7 velar and 2 ocular lappets in each octant. These

RHIZOSTOIkLE — CEPUEA.

653

lappets are similar each to each and are rectangular in outline, being separated by very slight indentations which are spanned by a web. Fairly deep grooves extend up the vertical rim of the exumbrella surface of the bell, between the lappets.

The arm-disk is as wide as the bell-radius and is 18 mm. thick. The free parts, upper, of the 8 bifurcated mouth-arms are each about 20 mm. long. At the center of the arm-disk we find 4. to I z or more tapering, somewhat flattened, wan-covered filaments which are about 25 mm. long and terminate each in a simple, pointed end. There are also numerous shorter filaments, ranging from about 15 to 5 mm. in length, all near the center of the arm-disk, and many still shorter ones between the numerous frilled mouths of the 8 mouth-arms.

There are 4 small, oval, subgenital ostia only about 2 mm. wide. The ring-muscles of the subumbrella are entire, but are very weakly developed. The central stomach gives rise to 8 large rhopalar and about 56 (7X8) somewhat narrower radial-canals, all connected one with another by a network of anastomosing vessels. The rhopalar canals proceed straight through this network, giving offsmall side branches to the adjacent radial-canals, but the inter- rhopalar canals tend to lose their identity in the network. There is no distinctly differentiated ring-canal. There is a unitary, cruciform, genital cavity opening to the outer world by the 4 genital ostia. There are many fairly large, reddish-brown dots over the outer surface of the arm-disk and reddish-brown streaks around the exumbrella warts. The color of the bell

FIG. 405. — Cephea ociostyla. Drawn by the author, from specimens taken by the Albatross at Jolo Anchor- age, Philippine Islands, in February and March, 1908.

A, B, and C, side views of exumbrella, showing variations in development of warts; D, rhopalium seen from subumbrella side.

is faded in formalin, but a color note states that the exumbrella bore numerous small, round, ocherous spots. When the bell is 15 mm. wide there are a few, small, scattered warts near the center of the exumbrella. There are 8 rhopalia set within shallow niches. The bell-margin between the sense-clubs is entire and there are no lappets. There are 8 quite wide rhopalar and 8X3 somewhat narrower inter-rhopalar canals, all set into communication bv side branches forming a marginal network. The 4 genital cavities are separate. The 8 bifurcated mouth- arms lack appendages either upon the arm-disk or between the frilled mouths. This young specimen was caught upon the surface under an electric light in Jolo Anchorage, Philippine Islands, on February 13, 1908.

Cephea octostyla var. coerulescens Maas.

Nelroitoma carulescen:, MAAS, 1903, Scyphomcdusen der Siboga Expedition, Monog. 1 1, p. 35, taf. 5, fign. 37,46; taf. ii,ftgn. 97, 103; taf. 12, fig. 109; 1906, Revue Suisse de Zool., tome 14, p. 101. — BROWNF., 1905, Fauna and Geog. Maldive and Laccadive Archipelagoes, vol. ^, p. 967.

The bell becomes at least 200 mm. wide. There are 8 marginal sense-clubs, each with a terminal entodermal concretion-mass and without an exumbrella sensory pit. No ocelli ( ?) In other respects the bell resembles that of Cephea octostyla having a central dome which bears about 10 wart-like projections. There are 6 to 8 round-edged, marginal lappets in each octant. The 8 mouth-arms are short, massive, laterally compressed, and curved outwards.

654

MEDI'S.K (IF THK WORLD.

Each mouth-arm bifurcates at its outer end and also gives rise to numerous very short, lateral branches upon its lower side. These side branches themselves branch somewhat dichoto- mously, giving a complex system ot mouth-bearing ramiih upon the lower side of the mouth- arm. There are two sorts of appendages between the mouths: small, thin, tubular appendages with prominent nettling-warts and larger, spindle-shaped appendages. These are, however,

very small in comparison with the size of the branches of the arms themselves.

In young medusae there are 4 separate, subgemtal cavities with 4 small, external ostia in the inter- radial sides of the arm-disk. In older individuals we find a very variable condition, the different quadrants of the same medusa being unlike; but it seems that a completely separated, subgemtal porticus, such as that found in Crambessa or Cotylorhiza, is never formed in Ce plica carulescens. The canal-system of the umbrella consists of 8 radial-canals in the radii of the 8 marginal sense- organs and 24 intermediate canals which give rise to numerous side branches, forming a network of canals which place all 32 vessels in communication one with an- other. There is no distinctly differentiated, annular ring-canal. The muscular system of the sub- umbrella resembles Cotvlorlnza in the form of the radial-muscle strands. The marginal ring-mus- cles are, however, very poorly developed.

The general color appears to be blue. A narrow zigzag band of fiery red, around the outer side of the arm-disk, lies above the subgenital ostia and bends down- ward (outward) at each interra- dius toward the subgenital ostium. Clusters of small, brown, oval

FIG. 406. — "Perirhiza nematophora.tt= Cephea cephea, after Kishinouye, in Journal College of Science Tokyo.

spots are found near the side of each subgenital ostium. This medusa is found in the Malay Archipelago and Maldive Islands, Indian Ocean.

The reddish dots found in the typical C. octostyla around the sides of the arm-disk have, in

this variety, fused into a solid band of color.

Cephea cephea.

Mtdusa cephea, FORSKAL, 1771;, Descript. Anim. Itin. Orient., p. 108, No. zz, Icon., tab. 30 (Non. Tabl. 29).

Medusa octostyla, LINNE, (Gmelin), 1788, Systema Nature, Ed. 13, Pars. 6, p. 3157.

Cephea rhizostomoideii, PERON ET LESUEUR, 1809, Annal. du Mus. Hist. Nat. Paris, tome 14, p. 361, No. loo.

Pohrhi-.a cephra+Diplopilus couthouyi, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 156, 158.

Cephea forsta/ea+C. conifera, HAECKEL, 1880, Syst. der Medusen, pp. 574, 576, taf. 36, fign. 3-6.

( ?) Cephea fusca, PERON ET LESUEUR, 1809, loc. cit., p. 361, No. 99.

( ?) Cassiopea fusca, DUSIMUER, 1835, Musee du Jardin des Plantes, No. in.

Perirhiza ncmatophora, KISHINOUYE, 1902, Journal College Sci. Tokyo, vol. 17, Art. 7, p. 14, plate 2, figs. 11-13.

KHIZOSTOM.E — CEPHEA. 655

Forskal gives a good, clear drawing of this medusa, which bears so close a resemblance to the figures of " Pt -lir/iizn nematophora" <>t Kishmouye that I am convinced the two are identical. The medusa is distinguished by the very deep rhopalar clefts in the bell-margin, its long tapering mouth-arm-filaments, and brown color. Gmelin erred in calling this M . octost\la, when he quoted from Forskal, for the latter's .\fi-Jusa octostyla is very different.

Bell 100 to 140 mm. in diameter. A large dome at apex of exumbrella, nearly as wide as bell-radius and covered completely with about 30 large, conical, pointed warts, many of which are bent near their pointed ends. The dome is surrounded by a wide, shallow ring- furrow, which separates it from the nearly equally wide, flexible marginal zone of the bell. The 8 sense-organs are set within deep niches in the bell-margin, as is well shown in Forskal's figure. There are So to 90 marginal lappets; in each octant 8 or Q large, oval, velar between 2 very small, pointed, ocular lappets; the velar lappers are united by a web, so that the bell- margin appears to be nearly entire. The small ocular lappets are deeply set inward centrip- etal to the margin.

On the subumbrella a radia'ing inner zone of folded ridges contains the radial muscles, and near the bell-margin is an unbroken zone of circular muscles. Arm-disk octagonal, nearly as wide as bell-radius. The 4 subgenital ostia are very small, compressed clefts. 1 here is a unitary, cruciform, subgenital cavity. The arm-disk has no canal-system of its own, and there are no mouths upon its central pans. The 8 laterally compressed, stout, adradial mouth-arms are somewhat shorter than the bell-radius. Their upper halves are neail\ coalesced where they arise from the arm-disk, but below they fork and each main branch branches profusely and curves upward. The numerous, frilled mouths are found on the lower, ventral sides of these mouth-arms and their branches. There are more than 100 long, tapering, hollow filaments with pointed ends. The largest of these arise from the arm-disk at the points of origin of the 8 mouth-arms, and they are as long as the diameter of the umbrella and hollow. Forskal figures 16 such filaments all apparently arising from the arm-disk and numerous smaller ones arising from between the mouth-frills on the arms, very much as does Kishmouye 127 years later.

The nearly circular, central stomach gives rise to 8 ocular and about 40 to 48 interocular radial-canals. The ocular canals are not wider than the others, but they ex'end straight out to the rhopalia, giving off numerous side branches into the network-zone of the bell; whereas the interocular canals lose themselves in this wide network of anastomosing vessels which form a broad zone extending from near the outer edge of the stomach-cavity to the bell-margin. There is no differentiated ring-canal. The network gives off many blindly-ending branches which extend downward into the radiating muscular ridges of the subumbrella.

Tin- margins of the velar lobes are brown, but Kishinouve finds that o'.her pans are colorless, although Forskal's medusa displayed some reddish-brown on its bell. Porskal describes this medusa from the Red Sea, and Kishinouve from Misaki. Japan, where it is found in winter. IV-ion and Lesueur's ('.. fn^-n. from Malabar and nonhwesrern Australia, is probably the same medusa; as is also Dtplopilits coulh<m\i Agassi/,, iSf>> it'onr. Nat. Hist. U. S., vol. 4, p. 158), from Hawaii. The medusa appears to be widely distributed over the Indo-l'acific region. Haeckel's Crplifii cnnijcrn from Samoa may be another name tor tin- same medusa, but its color is not stated and its marginal lappets appear to be indistinct, and the bell-margin to be practically entile, as in C. ,-n-rulfn. The decided resemblance, in other respects, between Haeckel's C. coniffra and Forskal's medusa \\ill appear in the following description.

"Cephea cephea var. conifera" Haeckel.

Cefhea coaiftra, H.\icKt.L, i S8o, Sy*l. Jrr M,,|u .„.,,. 576, taf. 36, fign. 3-6.— HAMANN, 1881, Jrn.i. /.oil . fur Naturw., ll.l. 15, p. 246 (anatomy of mouth-arms).

This is probably identical with ('i-j-iln-n if filial.

Bell 100 to 120 mm. wide, 30 to 40 mm. high. A thick-walled, flatly rounded, central dome upon the exumbrella bears 20 to 30 large and numerous small piotuherances and is separated from the marginal /out- of tin- exumbrella by a deep annular furrow. These solid, wart-like protuberances of the central dome are scattered irregularly over its entire surface, as in C. cirnili-ti, not arranged in 2 rows, as in ('. Juntokiiroa. 8 rhopalia are set within deep niches. 80 indistinctly developed, marginal lappets. In each octant 8 wide, flat, velar lappets,

656

OF THK WOULD.

flanked by 2 very small, rhopalar lappets. The lappets are so poorly developed that the bell- margin is practically entire and without notches, in this respect resembling C. ctcrulca. The octangular arm-disk is about as wide as the bell-radius, and the 4 subgenital ostia on its interradial sides are very short, narrow clefts.

The 8 mouth-arms arise in 4 pairs from the perradial angles ot the central part of the arm-disk, but separate widely, one from another, so as to project from the 8 adradial corners ot the sides ot the disk. The 8 mouth-arms are each about as long as the bell-radius and each one bifurcates near its outer end. Numerous short branches arise from the ventral sides of the mouth-arms and these bear the mouths. A single long, stout filament arises from each ot the 4 perradial corners of the ventral side of the arm-disk at the points of bifurcation ot the 4 primary mouth-arm canals. In this respect the medusa differs from C. ca:nil,-n, wherein there are 4 filaments in each perradius oi the arm-disk. There are also more than 100 long, slender filaments between the mouths. These filaments are longer than the bell- diameter. In the closely allied <7. cirrulca the mouth-arm filaments are very short and incon- spicuous. The radial-muscles ot the subumbrella are well-developed and form radiating,

lamella-like ridges as in C.ccerulea. There are numerous, fine, anasto- mosing radial-canals and a wide network of vessels near the mar- gin. Color (?)

Found at the Caroline and Samoan Islands, tropical Pacific. This description is presented to show that there are no appreciable differences between this medusa and Forskal's AleJusa cephea.

Cephea cephea var. dumokuroa Agassiz and Mayer.

Crf'heei diitnokuroa, AGASSIZ AND MAYER, 1899, Bull. Museum Comp. Zool.at Harvard College, vol. 32, p. 171, plates II, 12, figs. 36-39.

Netroslomti ilumokuroa, MAAS, 1903, Scypho- mcdusen dtrSiboga Expedition, Monog. 11, r. 38.

Bell 300 mm. wide, flat, and disk-shaped with sides vertical near the margin. A large promi- nent domeat center of exumbrella. The apex of this dome is smooth and without the wart-like protuberances seen in C. ccerulea and C. conifera; instead of which the protuberances of C. Juinokuroti are arranged in two ver- ticels, confined to the sides of the dome. The upper row of protuberances consists of about 8 large, solid, wart-like, bluntly-pointed projections, and below them is a zone of about 12 smaller warts not more than half as large as those ot the upper row. There is a wide, shallow furrow around the dome. 8 rhopaha are deeply sunken within marginal niches. Each sense- organ contains a terminal mass of white, entodermal concretions. There is no ocellus and no exumbrella sensory pit.

The marginal lappets are so shallow that one can barely distinguish them, but there are 8 scarcely perceptible, velar lappets in each octant, as in C. cacniL-a and C. coinft-ra. The arm- disk is about as wide as the bell-radius and there are 4 very small, round, subgenital osfia, with a unitary subgenital porticus. 8 short, bifurcated mouth-arms, each about as long as bell- radius; their free outer ends curve upward and the mouths are confined to the ventral sides of the arms, the frilled mouths being placed upon short branches which arise from the lower side of each arm. There are neither filaments nor club-shaped appendages, and in this respect the medusa differs from C. ca-nilea and C. conifera. The central stomach is a wide cruciform space above the subgenital porticus. 32 radial-canals arise from its margin and diverge into the sub-

FIG. 407. — " Cephea conifera" after Haeckel, in Das Syst. der Medusen.

IIIIIXiiSTdM.K CKI'HKA. 657

umbrella. 8 of these canals lead to the rhopalia and j are in each inter-rhopalar octant, instead of 7 as in <7. ctrruL-n. There is a wide zone ol anastomosing \essels near the margin. The central stomach also sends 8 canals downward into the arm-disk and this in turn to the 8 mouth-arms.

General color of medusa blue, as in ('. fa' nil en. The bare apex of the central dome is streaked longitudinally with blue, and a deep blue entodermal band of color extends around the sides of the arm-disk above the subgenital osfia. This blue band is especially wide in the adradii above the bases oi the 8 mouth-arms. The unbranched portions ot the radial- canals adjacent to the stomach and the canals of the arm-disk and arms are blue. The broad network ot anastomosing vessels near the hell-margin is dull coffee-colored and the frilled mouths arc of a deeper hue of the same culm.

A large swarm of these medusse was found upon the surface ofl Vamia r balavu Island, Fiji Islands, on November 25, 1897.

Cephea cephea var. coerulea Vanhbffen. Cephfa carulea, VANHOFFEN, 1902, Wist-en. Ergeb. deutsch. Ticfsce Exped. I'tildiriti, Bd. 3 Lfg. i, p. T5 'at. 4, fign. i;, 14.

Bell 57 mm. wide. A dome-like apex 14 mm. wide at the center of the exumbrella is surrounded by an annular furrow q mm. wide. The dome itself bears 6 large and about 30 small, rounded, wart-like protuberances, the largest of which are 2.4. to 5 mm. wide; numerous fine punctations between the warts. There are 8 rhopalia. No marginal lappets, bur 8 radial thickenings of the gelatinous substance at the margin in each octant. The 4 subgenital ostia are very small. The dichotomous mouth-arms are each 16 mm. long and bear trilled mouths on their ventral sides. There are 4 long filaments at the point of bifurcation ot each ot the 4 primary arm-canals, 16 in all; of these, the second and third are 2 to 3 times longer and much stouter than the first and fourth. Numerous very small filaments are among the mouths. The central stomach gives rise to 64 radial-canals, which break up into a wide, anastomosing network zone near the bell-margin. There are 8 rhopalar radial-canals and 7 inter-rhopalar canals in each octant thus differing from C. Jumvktiroa, wherein there are only 3 radial-canals in each inter-rhopalar sector. There is a broad, marginal annulus ot ring-muscles in the subumbrella, and centripetal to this is a wide zone of radial-muscles extending trom the supports ot the arm-disk to the zone of ring-muscles.

The disk, arms, and filaments are blue and the frilled-mouths are chocolate-brown.

Found at Dar es Salaam, east coast of Atnca (see fig. 408).

Cephea cephea var. setouchiana.

Microstylus setouffiianus, KISHINOI vv, 1902, Journal College Sci. Tokyo, vol. 17, Art. 7, p. 11, plates i, 2, figs. 8-10. .Vetrostotna selcucltianus, BROWNE, 1905, Fauna ami Geog. Maldive and Laccadive Archipelagoes, vol. 2, p. 967.

Disk 100 to 200 mm. wide with a prominent central dome nearly as wide as bell-radius and covered completely by 50 or more solid, pointed, wart-like projections of various sizes. This central dome is surrounded by a wide, annular furrow which separates it from the thin, flexible, outer zone of the exumbrella. 8 rhopalia. 6 to 8 flatly rounded, velar lappets flanked by 2 smaller, rounded, rhopalar lappets in each octant. 50 to 60 lappets, in all, upon the bell- margin. The 8 mouth-arms curve outwardly and upwardly in their lower halves. They are a Hide longer than the bell-radius and each one is forked, each of the main torks being nearly as long as the upper, undivided part of the arm. The forks give rise in turn to numerous pinnate branchlets. There are numerous small, short appendages among the trilled mouths, and those on the arm-disk at the ends of the perradial oral suture are longer, triangular in cross-section, and prickly in appearance. The 4 subgenital ostia are circular and much narrower than the spaces between them. The subgenital ca\it\ is unitary and 4-lobed, as in Cotylorhiza.

The central stomach gives rise to 8 lar^e rhopalar and 24 inter-rhopalar radial-canals, all of which extend straight outward to the bell-margin. All of the canals give oft side branches which form a wide, anastomosing network of vessels, the meshes ot which are mainly polyg- onal near the center, but rectangular near margin of disk. 8 canals arise trom the stomach at depressed areas near the sides of the perradial septa of the subgenital cavity. These canals

MKDUS.'E OF THE WORLD.

extend downward into the 8 mouth-arms and each give oft a horizontal branch which extends into the center of the arm-disk where they unite in a single short duct.

Each wait of the central dome is pigmented with lines of numerous, minute, brown dots converging toward the pointed apex of the wart. There are also brown dots on the sides ot the arm-disk. The oral frills are brown and the gonads pinkish.

Found in August and September in the Inland Sea, and at Misaki and Senzaki, Japan.

A shrimp is commensal with the medusa, hence its popular Japanese name "Yebi- kurage" (shrimp medusa).

Cephea typhlodendrium.

Netrostoma tvplilodendriun, SCHULTZE, L. S., 1898, Denkschr. Med. Nat. Ges. Jena., Bd. 8, p. 457, taf. 34, fign. lo-l2a. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 11, p. 38.

Bell flatly rounded, 110 mm. wide. The center of the exumbrella is occupied by a low dome completely covered with about 80 rounded warts of various sizes. There is no ring- furrow around the dome. The outer parts of the exumbrella are smooth. 8 marginal sense- organs. 80 marginal lappets composed of 64 rounded or cleft, velar lappets and 16 narrow sharp-pointed ocular lappets. The 8 mouth-arms arise from a thick arm-disk. The mouth- arms branch dichotomously and are laterally compressed. Small, spindle-shaped, sharp- pointed filaments are found only on the arm-disk. There are 4 very small, round, subgenital

409.

FIG. 408. — Ctphca drrulfa, after Vanhoffen in Valdi-cia Expedition.

FIG. 409. — Ctphta setouchiwui, Kishinouye, in Journal College of Science, Tokyo.

ostia and a unitary, subgenital porticus. The stomach gives rise to 32 radial-canals: 8 ocular, 24 interocular. The interocular canals give rise, distally, to blindly-ending side branches, peripherally to anastomosing branches; but the 8 ocular canals give off only the peripheral, anastomosing vessels. These ocular canals are wider than the interocular and extend straight through the marginal network to the 8 rhopalia, whereas the interocular vessels become lost in the peripheral network. There is no definite ring-canal.

Found at Amboina, Molluccas, Malay Archipelago.

This may be a well-defined species, for it appears to be distinguished from other members of the genus by its small, sharp-pointed, ocular lappets.

Genus COTYLORHIZA L. Agassiz, 1862.

Colylorhiza, AGASSIZ, L., 1861, Cont. Nat. Hist. U.S., vol. 4, p. 158. — HAF.CKF.L, 1880, Syst. der Medusen, p. 609. — CLAUS, 1883, Untersuch. Organisation und Entwick. Medusen, p. 60, Leipzig. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, pp. 27, 40. — MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. 1 1, pp. 32, 80, 89.

The type species is the well-known Cotylorliiza tuberculata (McJusu tuberculata Maori) of the Mediterranean.

GENERIC CHARACTERS.

Rhizostomata Jic/iotoma with 8 simple, bifurcated mouth-arms, the terminal branches of which branch pinnately. The 4 subgenital ostia are simple and funnel-shaped, and there

Kill/' ISTOM I) ( <>'n l.ulMIIX A. I',.V.I

is a single subgenital porticus. The appendages upon the mouth-arms are mounted upon pedunculated filaments. There are 8 marginal sense-organs and numerous radial-canals which anastomose laterally without any definite ring-canal in the adult. The sense-clubs have no ocelli and no exumbrella sensory pit. There is a unitary peripheral zone ot circular muscles and an inner /one ol radial-muscles in the subumbrella. 1 he exumbrella is smooth and without an a bora I "sucker-like" depression, but with a prominent central dome without wart-shaped elevations upon it.

This genus is sharply separated from (l<issirjf>i-n. with which it has often been confused. by its single, unitary, subgenital ponicus, its relatively simple bifurcated mouth-arms, and by having constantly 8 instead of an indefinite number of marginal sense-organs. Also there is no aboral "sucker" upon the exumbrella, such as is commonly seen in Cassiofea.

Cotylorhiza tuberculata L. Agassiz.

Plate 73, fig. 2.

Medusa tuberculata, MM KI, (!., 1778, Osservazioni Int. Polmonc Marino, p. 20. — LlNxt, (Gmdin), 1788, Systcma Natur.r, Ed. 13, Pars. 6, p. 31^.

Medusa tuber, MACKI, S., 1*25, Aiti Re.ile Acad. Sci. N'ap.ili, MI], 2, Partc 2, p. 74, tav. 4, figs. I, 2.

Ceplita f>ol\chroma, PERON KT I.* su H'R, 1809, Annal. du Mus. Hist. Nat. Paris, tome 14, p. ^'>i . I, \M\K» k, l 81(1, Hist. Anim. sans Vrrt., tome 2, p. 516.

Cassiofea borbonica, Dnii CIIIAU, iSj-,, Mi-nturie sulla storia e notomia dcgli animali scn/.a vertebre, N.ipi.li, M. in. 3. p. 75, tav. 3, 4, figs. 1-6; 1841 , Animali M n/.i MTI ., N.ip. >li, ti.me 7, tav. 140-141 . — KOWAI I VSKY, 1873, Mem. Imp. S of Nat. Hist., Mir i <"., nli 10, part 2, p. 3, plate 2 (Russian). — Di> PLTSSIS, 1881, Bull. Soc. Vaud. Sci. Nat., vol. 17, No. 86, p. 633, plate -, i (development i,{ egg-scyphostoma).— DE Mv.Rt JKOWSKV, 1882, An l.n . /. » 1. I. \pi-r. i-t (Jen. i Ac, tome 10, p.577,planche 29$, figs. 14-20 (development of spermatozoa). — CLAUS, 1883, Arbeit, /mil. In r .\\ n-n, H.! . ^, p. i fi.j, 2 taf., fign. l-ll (development of the cphyra); 1883, Organisation und Entwick. der Medusen, pp. 4;, ",, t.if. i^, tign. 106-1 1 1 (ephyra); 1890, Arbeit. Zool. Inst. VVien, lid. 9, p. 85, taf. 4-6; 1890, Wrhan.ll. /.mil. Bot.m. (iev 11. \Vn n. lid. 40, pp. 54-55 (development "(tin- -i \phostoma lan-a); 1892, Arbeit. Zuol. Inst. VVien., lid. [O, p. I (scyphostoma). GnAErri, 1884) Arbeit. Zool. Inst. Wien( Bd. 5i p. 343 (seasonal distribution). KMIIK, iss^, Rnuiil 2ool. Sui ^tome i.p. 403 (breeding habits of the medvis.i, .in. I nature uf the "selluw cells"). — VAN HI IK JN, i8S8, liibliothna /.milngira, H.I. i, II. I' ;. pp. 27, 40 (in the Red Sea). Htssi, 1895, Zeit. fur wissen. Zool., Bd. do, p. 441 , tat. 2 I , tie,n. 17-19; taf. 22. lirri. 2-. 28 (nervous system of the subumbrella).— HII.K LOW, R. P., 1900, Mem. Boston Soc. Nat. Hiet., vol. 5, No. 6, p. ;o.|. 1 1 i902,Zool.Anzcigcr,Bd.25, p. 637; 1902, '/.eit. fur wissen. Zool., Bd. 73, p. 302, taf. 20. 2 i ' irula).—

BETHE, 190-,, Allgcmeine An.it. nn.l 1'hvsi.il. Nervcnsystem, pp. 410, 414, 448, etc., fig. 8-,, 84, 8S, i|i. i-tc. (pi. the nervous system and of pulsation). MAAS, 1904, Result. Camp. Sci. Prince de Monacn. t.i . . :S, p. 58, planche 2. figs. 16-19; P'ate '> ^£- 47! !9°" Scvphnm.-dusen der Siboga Expcd., Monog. n, p. -,2, t.il. S, tign. (19,70. Hoi MIK, 1907, Bull. Imtit. Oi-e.m.igi.ipli. Pii m e de Monoco, No. 93 .

( ?) Cassiofea enroll iflora+ C. canariensis, TILKSIUS, 1829, Nova Acta. phys. med. N. C., tome 15, pp. 265, 285, tab. 73.

Cephea tuberculata, ESCHSCHOLTZ, 1829, Syst. der Acal., p. 56.

Cefhea wagentri, WILL, 1884, H.ir.i • Terge tm.i , p. ;S. Hi s, n, i 851, Anat. Entwick!. \virbell. Seeth., p. 3O,taf. 2, 3.— FK^N c/n s, 1852, Zeit. fiir wissen. Zool.. H.I. 4, p. 118, taf. S, fign. 1-4 (siphostoma larva).

Cassiofea borbonica, GH;HM \i u, 18^4. Generationswechsel Medusen, p. i, taf. 2, fign. 32-35-

Cotylorhiza tuberculata, AI;ASSIZ, L., 18(12. font. Nat. Hist. U. S., vol. 4, p. 158.— HAMANN, 1881, Jen.i. Z.-ii. fur Narunu n, B I. 15, p. 254, t.if. <i, fign. 8, 9; taf. 10, fign. 19-23, 34, 35; taf. n, fign. 24-28 (structure of the mouth-arms).

Cotylorhiza luberculata, and C. ambulacrata ( ') HAM kti , 1880, Syst. der Medusen, pp. 610, hi I.

Cotylorhiza borbonica, GOTTE, 1 88;, /.....]. An . .• U. I. 8, p. 554; 1887, Abhandl. Entwich. ,|. i Ilinir, Heft. 4, Leipzig, 79 pp.;

1893, Zeit. fur wissen. Zool., Bd. 55, p. 645, taf. 28, 29 (embryology).

Bell usually not more than 150 to 170 mm. in diameter, though according to \\ ill it may become 300 mm. wide. The dimensions of a large medusa found at Naples on December iS, 1907, were as follows: Hell idX mm. wide, arm-disk 88 mm. wide, each mouth-arm 4') mm. long and 54 mm. thick (dorso-ventrally). The gelatinous substance is \ei\ rigid. The exum- brella surface is smooth and without wart-like projections.

The center of the exumbrella is occupied by a smooth, elevated dome, somewhat flatter than a hemisphere and about as wide as radius of disk. Around the outer edge of this dome is a depressed region forming a gutter-like ring, somewhat lower than the pans ot the bell nearer the margin. There are 8 marginal sense-organs, which lack an exumbrella sensory pit and base no ocelli. The sense-club has a very large, bag-like ventral bulb and contains a terminal mass of orange-colored entodermal concretions.

The marginal sense-organs are Hanked by in short, blunt, oval rhopalar lappets. Tin it- are typically 1O velar lappets in each octant, the middle d of which are sometimes, but not always, cleft. The outer edges of these lappets are subrectangular with bluntly-rounded angles. The primary clefts lni\\<ni the lappets are fully twice as long as the s<ruml;n\ delis of the 6 middle lappets; but all the clefts are bridged over by a web of subumbi el la tissue, so that they are not complete cuts, but meie grooves upon the exumbrella. 1 he id vel.n

600

MEDUSAE OF THE WOULD.

lappets adjacent to the 16 rhopalar lappets are fully twice as wide as the others and are rarely cleft. The actual number of marginal lappets is quite variable, but we may say that there are typically 96 primary lappets, of which 48 are typically cleft. Counting these clefts we would then have 18 lappets per ociant or 144 in all. The bell-margin usually bends at right angles to the general surface of the exumbrella; subumbrella surface convex.

Arm-disk octangular with re-entrant angles and sharply set off from subumbrella. It is thick and about as wide as radius of bell. Thus in a medusa 168 mm. in diameter the arm- disk was 88 mm. wide. 4 simple, small, oval, subgenital ostia on interradial sides of arm-disk are not much wider than the width of a marginal lappet. The 8 adradial mouth-arms are bluntly simitar-shaped in general outline, are laterally compressed, and only about half as

FIG. 410. — Cot\lorhiza tubfrculata, from life, by the author, at Naples Zoological Station, December, 1907.

A, oral view with all but one of the mouth-arms removed. The muscular layer is also removed over the area on to left side of the figure in order to show the canal-system. B, section through medusa showing central stomach and unitary subgenital space below it. C, cross- section through subgenital space (sparsely dotted) and stomach (with thickly placed linear dots); showing the 8 ostia of the mouth-arm canals. D, mouth-arm cut off from arm-disk and viewed from cut end. E, club-like appendages among the frilled mouths. F, sense- organ seen from exumbrella side.

long as bell-radius. They are somewhat thicker (downward) than wide and arise from the arm-disk at 45° apart. Thus in a medusa 168 mm. in diameter the mouth-arms were each 46 mm. long and 54 mm. thick. Each mouth-arm bifurcates near its base and each of the two main branches gives rise to about 10 to 14 side branches, which in turn give off 30 to 40 smaller branches, and these again to 100 to 150 smaller branches, which branch still further dendritic- ally. The farther out the branches the more dendritic and the less dichotomous is their mode of branching.

A large number of short, club-shaped appendages between the frilled mouths terminate in bluntly conical to flatly expanded, disk-like ends covered with small, wart-like tubercles.

Kill/us Ki\I i: mTYI.oUHIZA. (5(51

Besides these short appendages, less numerous but somewhat larger ones terminate in a flattened hall-like to disk-like end set in a socket. At the point of bifurcation of each of the 8 mam mouth-arms is a filament which is circular in cross-section and nearly half as l<m» as the mouth-arm itself. Tins filament tapers gradually from base to tip, but usually terminates in a swollen end. Centripetal to these 8 main filaments are 3 to 5 other, somewhat shorter filaments arising between the frilled mouths of each mouth-arm. Near and at the center of the arm-disk there are numerous slender filaments, about one-third as long as the main filament, which terminate in expanded disk-like conical ends.

A unitary, cruciform, suhgenital space opens outwardly at the 4 suhgenital ostia. Thus it is possible to pass a probe into any one of the subgenital ostia and out through tin oni- on the opposite side of the arm-disk without penetrating any tissues of the medusa; the subgenital space being actually outer world (C, fig. 410). The complexly folded, ucmtal membrane is developed upon the sides and upper floor of this subgenital space, and thus upon the lower floor of the central stomach.

The central stomach is large, occupying the spacious cavity of the central dome of the exumhrella ( B, fig. 401). 1 1 to 13 radial-canals per octant (88 to 124 in all) arise from the margin of this central stomach and extend outward to the bell-margin. There is no dis- tinct ring-canal, but instead there are numerous, lateral anastomoses between the radiating canals, forming a complex network of vessels under the floor of the subiimbrella. The main canals of the 8 mouth-arms empty by S adradial openings into the central s'oinach. I'.ach of these mouth-arm canals bifurcates, and the two main branches give rise to numerous, lateral diverticula which lead to the gutters of the frilled mouths.

I here is a well-developed unitary, marginal ring of circular muscles and an inner zone of radial-muscles in the subumbrella. Bethe, 1905, has shown that \\hen the medusa pulsates these inner-lying radial-muscles contract ht-fui;- the ring-muscles, though the latter lie nearer to the sense-organs, from which the contraction-impulse arises. This more rapid response of the radial-muscles is due to the fact that their latent interval between the reception of the stimulus and their response is less than in the case of the circular muscles. Bethe also finds that the normal pulsation consists of 80 to IOO contractions at fairly regular intervals with periods of total rest between them. These are then followed by a pause which lasts as long as 3 to 20 of the normal pulsations. For further details of the character of the pulsation, tin- reader should refer to Rhizostoma /n/lnin.

The bell of this medusa is rich oli\e, tending to orange, 01 to hrowiiish-vellow. being especially dark and brownish on dome-like apex of the exumhrella. The rich yellow color is found on both exumbrella and subumbrella, and is due to the presence of numerous M ll<>\\ to brown plant cells (Zoochlorellte) which float in the canal-system and infest the enioderm of the medusa. Claus, 1885, finds these cells in the 8 lobed eplnia when onlv 1.5 to i mm. wide.

The arm-disk and mouth-arms are usually pale milky-white tinged with delicate creamy- yellow. The free outer edges of the mouths are tinged with purple vai\in«;to blue in \iolet. The terminal portions of the appendages, which arise between the frilled mouths, are deep blue tending to purple, or violet.

This medusa is found in the Mediterranean, bur is quite capricious in its appeal a nee. being at times very rare. According to CJraeHe it is not seen everv year in the Adriatic .it I ncste, but adult medusae are usually seen from July to September, while small ones are found in July and August. At Naples adult medusa- are commoner from August to ( (ctoberthan in winter, when they become \er\ rare, being only occasionally found in mid-winici. Keller is of the opinion that this medusa is a deep-water species which only occasionally comes to the surface when sexually mature, ami that tin- \OIIIIL; lemam near the bottom of the sea. Yan- hoften, 1888, records the capture of a young individual of this medusa at \ssab in the Red Sea on June 10, 1885. The medusa must have been introduced into the Red Sea through tin- Sue/ (.'anal. It has also been found in the Atlantic, near the Canary Islands. (See C. ;»//'/<- /.;. iiilii I laeckel.)

The development of this medusa has been studied by Busch, Frant/.ms. ( ic^cnb.iu i . Kowalevsky, Claus, (ioette, du 1'lessis, Mem, and ntheis, and has furnished some of the e\ i deuce for a conf roveiM between Claus and ( ioette concerning the development of the ;;ast n>- vascular cavity of the sc\ phostoma.

662 MKDUS.E OF THE^WORLD.

The young larvae are set free from the mouths of the mother medusa as planulae or young gastrulae. Segmentation is total and nearly equal. The gastrula is formed by invagination as in the case of Aurellia. The free-swimming planula is pyriiorm to oval, flattened laterally, and ciliated externally. The entoderm of the planula is entirely encased by the ectoderm through the closure of the blastopore, and thus the planula is a two-layered sac which attaches itself to the bottom by means of its broad anterior end, and then loses its cilia.

An invagination of the ectoderm takes place at the posterior (now uppermost) end of the planula. According to Goette the entoderm is also evaginated at the same time in such manner that two backwardly projecting pouches remain in the plane of the wide lateral diameter, while these pouches are absent on the flat sides of the larva. The ectodermal invagination forms the mouth and oesophagus; while the entodermal evaginations form the first pair of lateral stomach-pouches. An opening is soon iormed where the invagmated ectoderm has fused with the entoderm, and thus the throat-tube is placed in communication with the central stomach. The second pair of gastric pouches now arise 90° apart from the first and, according to Goette, are produced by evagination entirely from the ectoderm ot the lower end of the throat-tube.

Hyde, 1894 (Zeit. fur wissen. Zool., Bd. 58, p. 521), finds, however, that in the case of Aurellia only the upper floor of the second pair of stomach- pouches is formed from the ectoderm of the throat-tube, their lower (aboral) floor being of entodermal origin and derived from the wall of the primitive stomach. Hyde 's research appears to be very care- fully prepared, and it is probable that the second pair of stomach-pouches in Cotylorhiza is of mixed (ectodermal and entodermal) origin as in Aurellia. The apparent analogy between the ectodermal oesophagus of the young scyphostoma and that of the Anthozoa is very interesting, for it may imply a close generic relationship between the Anthozoa and the Scyphomedusae.

In this connection we must, however, give due weight to the work ot the Claus-Had/.t school (see Genus Chrysaora) who find that the 4 primary stomach-pouches and the lining ot the throat are wholly of entodermal origin, and that therefore the scyphostoma resembles the hydropolyps more closely than the Anthozoa.

The scyphostoma develops 1 6 tentacles and then gives rise to buds which grow out from the sides of the body. The wider end of the pyritorm bud is adjacent to the parent scyphostoma, and the mouth is at this broad end. The bud is set free and swims, rotating through the water with its narrow posterior end directed forward. Soon, however, the bud attaches itself to the bottom by means of its narrow aboral end and then develops into a new scyphostoma.

This asexual development of lateral buds by the scyphostoma of Cotylorhiza seems to be a normal process and is described by Goette, 1887, p. 24, and Claus, 1892. Claus, 1892, reared Cotylorluza in an aquarium and found that eggs laid at Trieste in September developed into scyphostomae with 16 tentacles and then began to produce lateral buds in the following July. They strobilated in August. The strobilization is monodiscus, the scyphostoma giv- ing rise to one ephyra. The 8 marginal sense-organs are apparently developed out of the bases of the 8 perradial and interradial tentacles, while the 8 adradial tentacles degenerate and are absorbed. A similar process takes place in Cassiopea xamachana, according to R. P. Bigelow, 1900. The gelatinous substance is secreted by the entoderm.

Claus, 1883, has studied the young ephyrae of Cot\lor/uza tuberculata. When only 1.75 mm. wide the ephyra has a simple 4-cornered mouth similar to that ot the single-mouthed Scyphomedusae. There are 8 long, slender, cleft lobes in the radii of the 8 marginal sense- organs. The central stomach gives rise to 16 blindly ending radiating diverticula, 8 in the radii of the marginal sense-organs and 8 adradial in position. There is no ring-canal. These canals are lined by unicellular yellow-brown algae (ZoochlorelLr). There are 4 gastric cirri, one in each interradius. The 4 lips are simple and cruciform and devoid of a marginal fringe of tentacles. When about 2.25 mm. in diameter the oral fringe of tentacles begins to develop around the edges of the still cruciform mouth. When 2.5 to 3 mm. wide the ring-canal develops by fusions between the adjacent edges of the 16 radiating canals, and 8 adradial velar lappets begin to grow out from the deep notches between the 8 primitive ephyra-lobes.

When 3 mm. wide each quadrant of the cruciform mouth is bifurcated twice, giving 16 terminal forks to the entire mouth. The central mouth, however, still remains open. At this

1(III7.0ST<>M.K — COTYLOKHI/A, POLYRHIZA.

stage there are still only 24 lappets, 16 rhopalar anil S velar, When 4.5 to 5 mm. in diameter the ephyra has 8 (4 pairs) of cleft mouth-arms and the ring-canal has become unrecognizable, owing to the fusion into a network of numerous, lateral vessels which arise from the 16 radial- canals. It is evident that at first the ephyra is like that ot the single-mouthed Scyphomedusz and that only later it acquires the characters ot the multi-mouthed Rhizostomae. This is true of all known ephyrae of the Rhizostomae, and it furnishes the strongest argument for the theory that the Rhizostomae have been derived from the more simply organized, single- mouthed Scyphomedusae.

For further details of the development of (.'ntylni luzn the reader should consult the papers of Claus, (joette, Hein, and Ko\vale\sk\ .

Bouvier, 190", finds Tnii-linrus to he commensal with this medusa.

Haeckel's Cotylorhiza ambulacrata described horn a preserved specimen trom Lessona, Canary Islands, Ailantic Ocean, appears to me to he identical with (1. tnli,-r. nlnt.i. heing well within the limits of variation of the typical medusae found at Naples.

Genus POLYRHIZA L. Agassiz, 1862.

Polvrhisa, AGASSIZ, I.., 1862, Cont. Nat. Hist. I'. S., vol. 4, p. l 56.— HAFTKEI., 1880, Sv-i. ,|IT Mc.luvcn, p. ^-d.— Y*MiiJ> fr.N, 1888, Bibliothcca Zoologica, Hcfi. 3, p. 40. M**s, i:>o\, Scyplinini-ilusrn di-r Siboga Eipr.lition, Mmm!.1. 1 1, pp. 32, 81.

GENKRIC CHARACTI KS.

Rhizostomata Jicliototnn with mouth-arms hifurcated two or more times. Exumbrella without a dome hut with a central concavity and with radiating furrows. Numerous simple filaments between the mouths. 8 rhopalia. Numerous radial-canals and a wide marginal network of vessels.

Homopneusis fronJosa Lesson and Orythia in<:<il<ji Ouoy and Gaimard are believed by Haeckel to belong to the genus Polyrhiza, but the descriptions and figures of these medusa; are so vague, fanciful, and evidently inaccurate that we can not consider them. One should consult Lesson, R. P., 1829, Voyage de la Cotjiiillf, Mollusques, plate 12; and Ouoy et Gaimard, 1833, Voyage d YAstrolabe, Zoophytes, tome 4, p. 297 (not plate 25, figs. 6 to 10; these are mollusca).

Polyrhiza vesiculosa L. Agassiz.

Ceflira resiculosa, EHRFNBF.RG, 1835, Abliamll. Bcvlin AcaJ., p. 160.

Pol \rhiza vcsiculosa, AC.ASSIZ. I.., 1862, Cont. Nat. Hist. U. S., vol. 4, p. l 56. — HAMANN, O., 1881, Jena. X.i'ir . fur \,iumv.,BJ. i ;;, p. 247, taf, 9, fig. 7 (anatomy of mouth-arms).

Bell 50 to 60 mm. wide, flat, with a pit at center of exumbrella. 52 dichotomous, radiating furrows are separated by a deep annular furrow from the equally wide marginal zone of the exumbrella. 8 rhopalia. 80 lappets. In each octant are 8 rectangular velar ami l small rhopalar lappets. The mouth-arms branch dichotomously 4 to 6 times. I here is a large cluster of long, simple filaments at the center of the arm-disk. 32 radial-canals, 8 large rhopalar and 24 narrower canals, all connected one with another by a wide-meshed network of anastomosing vessels. There is no definite ring-canal.

Bell rose-red, knobs of mouth-tentacles brownish-black. Filaments transparent. Found in the Red Sea, at Tur and Suez.

RHIZOSTOMATA TRIPTERA Vanhbffen, sensu Maas, 1903.

Rliizostomata lriflera+ R. trigona, VANH"> ft N . tNSS, Bihh. .tin > .1 /.. » il ifii .1. B.l. i. Hi-fi. ;. pp. 41, 44- Rhisoslomala Iriftrra, MAAS, H)O',. Si \ phoim \lusra ilcr Siboga Elpi'.l.. M"ii"i;. II, p. 46.

Rhizostomae in which the lower parts of the 8 separate mouth-arms are 3-winged or Y-shaped in cross-section, being expanded in a ventral and 2 dorsal lamellae. The 3 lamellae narrow outwardly and meet in a point at the lower end of the arm. The frilled mouths are borne upon the 3 lamellae, especially along their free edges. The mouth-arms do not bear scapulets. The ring-muscles of the subumbrella are pn\\< iliil and the radial-muscles weak.

There is no sharp line ot demarkation between the Rhizostomata dichatoma with mouth- arms V-like in cross-section and the Rhizostomata trif>t,-ni wherein the arms are Y-shaped in

664

MEDTTS.E OF THE WORLD.

Fie. 411. — Diagrammatic representation of the shape and position of the mouth-arms in the Rhizostomata triptera.

cross-section. The two groups may, however, be maintained apart more for convenience of classification than because of any non-intergrading distinction between them.

Indeed the chief distinction between them is that in the Rhiwstomata dichotoma the radial muscles are powerfully and the circular muscles weakly developed whereas in the Rhizostomata triptera the reverse is the case, the circular muscles being the more powerful. Another distinction is that in the Rhizostomata dichotoma the axial duct of each mouth- arm simply bifurcates sending a branch to each arm of the V-shaped lower part of the mouth-arm. In the Rhizostomata triptera, however, each axial duct gives off 3 lateral branches which extend downward along the lines of the 3 rows of frilled mouths and usually rejoin the axial duct at the lower end ot the arm. This may be made clearer by saying that in the Rhizostomata triptera the arm is Y- shaped in cross-section, and the axial duct passes down through the middle of the Y while its 3 lateral branches extend down near the 3 ends of the Y. In the Rhizostomata dichotoma, however, a single duct extends down in the angle of the V and sends off 2 branches into the arms of the V (see text-figures 404 and 411).

The genera are very closely related, being distinguished by the presence or absence of appendages upon the mouth-arms and by the arrangement of the canal-system. A description of the genera follows :

Catostylus L. AGASSIZ, 1862. Neither clubs, filaments, nor other appendages upon the mouth-arms. The network of canals on the inner side of the ring-canal ends blindly -without connecting with the stomach.

L\chnorhiza HAECKEL, 1880. Similar to Catost\lus but with filaments, and no clubs upon the mouth-arms.

Crambtone MAAS, 1903- Similar to Calost\lus but with clubs and filaments upon the mouth-arms.

\lastigias L. AGASSIZ. Each mouth-arm terminates in a naked club-shaped extremity. Numerous clubs or filaments among the mouths. The network of canals arising from the inner side of the ring-canal connects with the stomach.

Pseudorhiza VON LFNDENrELD, 1882. Similar to \lastigias, but without lateral clubs or filaments among the mouths. A terminal club present. The canals which arise from the inner side of the ring-canal between the radial-canals end blindly without connecting with the stomach.

Phyllorhiza L. AGASSIZ, 1862. Mouth-arms with lateral filaments, but without clubs, as in Lychnorhiza. Canal system as in \fasligias.

Versura HAECKEL, 1880. Mouth-arms with clubs and filaments as in Crambtone. 4 perradial canals arise directly from the stomach, but the 4 interradial canals result from the fusion of a network of vessels which arise from each inter- radial side of the stomach. No ring-canal, but a marginal network of vessels. An outer and an inner zone of ring- muscles with an annular separation between them.

Lobonema, gen. nov. Marginal lappets of the bell elongated so as to resemble tentacles. Mouth-arm membranes per- forated. Emmbrella covered with papillae.

Genus CATOSTYLUS L. Agassiz, 1862.

Catostylus+ To.voclytus + Rhacopilus, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 152, 153.

Crambessa, HAECKEL, 1869, Zeit. fur wissen. Zool., Bd. 19, p. 509. — VON LENDENFELD, 1888, Zeit. fiir wissen. Zool., Bd. 47, p.

231. — BROWNE, 1905, Report Pearl Oyster Fisheries, Gulf of Manaar, p. 519. Toxocl\tus+ Crambessa, HAECKEL, 1880, Syst. der Medusen, pp. 585, 619. Crambessa+Loborhiza, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, pp. 28, 41, 44; 1902, Wissen. Ergeb. Valdiria

Eiped., Bd. 3, Lfg. i, p. 51. Toxoclytus+ Crambessa+ Loborhiza, MAAS, 1903, Scyphomedusen Siboga Exped., Monog. II, pp. 47, 61, 80, Si.

The type species is Catostylus mosaicus of Australia, first described as Cephea mosaica by Quoy and Gaimard, 1824. Agassiz designates this as the type of the genus.

GENERIC CHARACTERS.

Rhizostomata triptera the mouth-arms of which bear neither clubs, filaments, nor other appendages. 16 radial-canals, 8 rhopalar, and 8 adradial. The rhopalar canals extend to the bell-margin, but the adradial canals end in the ring-canal. On both its inner and outer sides the ring-canal gives off anastomosing vessels which may join with the radial-canals, but which do not connect directly with the central stomach.

RHIZOSTOMJB — CATOSTYLUS.

till.-,

Among characters of minor importance, the marginal zone of circular muscles in the subumbrella is only partially interrupted in the 8 principal radii. There is an exumbrella pit with radiating furrows above each sense-club.

VanhofFen, 1902, shows that Haeckel's Crambessa and Toxoclytus are identical and must be merged. The only possible distinction appears to be that in Toxoclytus there are 4 separate genital sacs, whereas in Crambessa there is a unitary, cruciform genital cavity.

Catostylus is very closely allied to I.\\ hnorhiza and Crambione, being distinguished solely by having neither filaments nor clubs upon the mouth-arms.

Haeckel's Crambessa is equivalent to the genera Catostylus, T'i\n>'l\tus, and Rhacopilus of L. Agassiz, 1862. The name Catostylus takes precedence over all of the others, and 1 laeckel should have used this name instead of inventing a new one.

The lower ends of the mouth-arms of C. orsim and C. stiililniuiiiii are dc\oid of frilled mouths and the extremity is blunt, triangular, and naked.

Medusae of Catostylus are often found in brackish or muddy harbors. They are often infested with commensal plant-cells which may give them a peculiar opaque yellow-brown coloration as in C. mosaicus in certain parts of Australia; for von Lendenfeld finds that m the harbor of Melbourne the medusa is not infested with plant-cells and is deep cobalt-blue in color, whereas in the harbor of Sydney it is infested and is opaque, light yellow-brown. I have also seen a swarm of these cobalt-blue medusa; in Brisbane Harbor, Queensland.

It is possible, as Vanhoffcn surmises, that "Cephea" Jnht.-iiillii Reynaud (1830, Lesson's Centurie Zoologique, p. 75, planche 23) may be a C<it'i\t\'lt<>. but the description and plate are so unsatisfactory that I think knowledge will be advanced by dropping the species. It comes from Pondichery, Indian Ocean.

C.,iti>st\his is abundant in the Indo-Pacific region, but only 2 or 3 species are known from the Atlantic coasts of Africa and southern Europe, and not one has been found in North

Synopsis of the Forms of Catostylus.

	C. cruciatus.	C. palmipes.	C.tagi,	C. pictonum C.ugi(?).	C. mosaicus.
Diameter of bell	1 20 to 150	64	500	400	35°
in mm.
Shape of bell, .in 1	Hemispherical, with	Hemispherical^ with	Flatter than a hemi-	\\'iili regularly rcc-	\i-arl\ IH nip.pheri-
character of <-\-	deep radiating fur-	fine granulations.	sphere with den.lri-	t.uiL'ul.ir i-li-\ atiori1-	cal, covered \\ith
umbrella surface.	rows.		tically branching	bordcrevl by fur-	coarse granulations.
			furrows.	rows.
Number of lappets	Six; 4 large triangu-	Kight; 6 large square	Ten; 4 pairs of large,	Ten; 4 pairs of large	V.iri.iblr, about 16
in each octant of	lar velar, 2 very	velar, and 2 »\ ,d	triangular vel.ir.	triangular velar.	oval, long, all sim-
bell-margin.	small ocular.	ocular.	an,l ; small, point-	and i small, pointed	ilar each to each.
			ed ocular.	ocular.
Length of mouth-	l to 0.5	r±	2 r	— 2 r	I to 0.5
arms in terms of
bell-radius (r)
Length of j-wini;-	4	6	3 to 4	j to 4 ?	6
ed, pointed, Imvn
end of each arm
in terms of lentil
of simple, cylin-
drical, upper part
of arm.
Color.	Be'l yellowish-white	?	( )pale- cent vi'llnw or	Y. 11 ••-', i h on	Bell an.l arms yel-
	Gonads and nng-		bluMi-'Aliitr. Some-	cent greenish-	lowish-white.
	i .in.il n^e-rrd, <>r		time brown.	whire. rarely	Op.i.pir. Sonir-
	with bluish-\\ liite		Ridges of exum-	reddish-yellow.	> nbalt-blue.
	bell, deep blue l.,p-		biell.i purpl<	, ,1 ' ,»
	1" : , ui.l red		brown. Gonads	yellow.
	mouth-frills.		yell"
\\ here found.	Coast of Brazil,	Northern co.i i <>t	In harbors from	Hrittanv, Atlantic	lit CO! • ••{ Aus-
	harbor of Km ,!••	Australia t<> Am-	Portugal t-i Si-nc- CO3 ' 1 i.tnee.	tralia, Brisbane to
	Janeiro.	boina.	gambi.i, \in- I.	\ , U8t,	Melbourne. In
					large swarms in
					harbors.

MEDUSAE OF THE WORLD.

Synopsis of the Forms of Catostylns — Continued.

	C.stuhlmanni	C. orsini.	C. stiphrop- terus.	C. viridescens	C. ornatellus.	C. tripterus.	C. purpurus.*
Diameter of	200	'5	IOO	80	?	5°	"5
bell in mm.
Shape of bell	Hemispherical	Flatly round-	Flat, with	Hemispherical	Flatly round-	Hemispherical	Flatly round-
and character	surface gran-	ed, smooth.	smooth sur-	with smooth	ed, granular		ed, smooth
of surface of	ular with		face.	surface.	surface with		surface.
exumbrella.	sharp pointed				lines over
	projections				lappets.
	on lappets.
Number of lap-	Fourteen; 12	Eighteen; 16	Seven; 5 large	? lost.	Ten; 4 pairs	Six; 4 wide	4 cleft, and 2
pets in each	long, rounded	long, sharp-	cleft velar,		of large,	quadratic	simple velar.
octant of bell-	velar, 2 short,	pointed velar,	and 2 slender.		bluntly point-	velar, and 2	and 2 rho-
margin.	small ocular.	and 2 smaller	sharp-point-		ed velar, and	narrow, long,	palar lappets
		ocular.	ed ocular.		2 small, sharp	projecting	in each oc-
					pointed ocu-	ocular.	tant.
					lar.
Length of	I to 0.5 r	r	— r	r	0.66 r.	r	0.75 r.
mouth-arms
in terms of
bell-radius(r).
Length of 3-	6	3	5	5	i	o-S	5 to 7
winged,
pointed, lower
end of each
arm in terms
of length of
simple cylin-
drical upper
part of arm.
Color.	Bell yellowish-	?	Exumbrella	Bell sea-green.	?	?	Uniform dark
	brown, milky-		with 4 per-	Arms color-			brownish-
	yellow with		radial areas	less. Mouths			purple.
	purple-brown		of brown	dark-violet.
	blotches and		spots.
	streaks. Arms
	colorless.
	Mouths
	brownish-
	purple.
Where found.	4 miles above	Assab, Red	Tern ate,	Mouth of Pen-	Near Puna	Fernando Po	Manila Bay,
	mouth of	Sea.	Malay Arch-	gami River,	Island, Guay-	Island, coast	Philippine
	Quilimane		ipelago.	East Africa,	aquil, Equa-	of Guinea,	Islands.
	River, East			in November,	dor.	West Africa.	Common.
	Africa, Feb-
	ruary to
	March.

American waters. There are a number of local races, as is the case with Cassiopea, which also thrives in harbors.

Catostylus mosaicus L. Agassiz.

Cephea mosaica, QUOY ET GAIMARD, 1824, Voyage de VUranie, Zoologie, p. 569, planche 85, fig. 3.

Rhizostoma mosaica, HUXLEY, 1849, Philosoph. Trans. Roy. Soc. London, pp. 422, 432, plate 38, figs. 26, 27; plate 39, figs. 28-34.

Catostylus mosaicus + C. wilkesii, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152.

Crambessa mosaica, HAECKEL, 1880, Syst. der Medusen, p. 622. — VON LENDENFELD, 1883, Annals and Mag. Nat. Hist., ser. 5, vol. l 2, p. 259 (neraatocysts in the gelatinous substance); 1884, Proc. Linnean Soc. New South Wales, vol. 9, pp. 428, 926; i888,Zeit.fiirwissen.Zool.,Bd.47, p. 231, taf. 19, fign. 10, 13; taf. 2i,fign. 21, 23; taf. 23, fign. 44-46, 51, 58, 59; taf. 24, fign. 63-65; taf. 25, fign. 66-78; taf. 26, fign. 82, 83, 93, 96, 97; taf. 27, fign. 108, 109, 111-113, 1 15-1 19 (detailed descrip- tion).— AGASSIZ, A., AND MAYER, 1898, Bull. Museum Comp. Zool. at Harvard College, vol. 32, p. 16, plates 2, 3, 5 figs. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. II, p. 47.

Bell fully 250 to 350 mm. wide, somewhat flatter than a hemisphere when expanded. Exumbrella covered with coarse granulations. 8 rhopaha without an ocellus, but with an exumbrella sensory pit having radiating furrows in its floor. There are about 128 long, oval, marginal lappets, about 16 in each octant, all similar each to each and with smooth exumbrella surfaces. Arm-disk somewhat wider than bell-radius. There is a unitary subgemtal cavity.

RHIZOSTOM.E — CATOSTYLUS. 667

A gelatinous papilla is found upon the subumbrella on the outer side of the opening of each subgenital ostium. The 8 mouth-arms are about 1.5 times as long as bell-radius. The laterally compressed, simple, upper part of each arm is only about one-sixth as long as the j-winged, tapering lower part. The 3 expanded membranous lamellae of the lower parts of the arms are 1 20° apart, and their free, outer edges branch profusely and bear the frilled mouths. The mouth-arms taper to a pointed end below. No clubs, filaments, or other appendages. The mouths are bordered by small knobbed tentacles, which wave incessantly. 16 radial-canals leave the cruciform central stomach and are connected by a ring-canal which gives oh\ both on its outer and inner sides, an anastomosing network of vessels which fuse with the radial- canals, but do not extend inward to the margin of the stomach.

This medusa is normally cobalt-blue, but in Port Jackson, New South Wales, Australia, it is infested with plant cells (Zooxanthellee), which give it a uniform creamy or brownish- yellow color except along the upper edges of the wing-like folds of the mouth-arms, where the deep blue color appears. In Brisbane Harbor and at Melbourne, Australia, the medusa is not commonly infested with plant cells and is deep cobalt in color.

C. mosaicus occurs in vast swarms in the harbors and estuaries of the Australian coast from Brisbane to Melbourne during the Australian summer and autumn.

It swims by an incessant series of pulsations of its bell-rim and tends to oppose the current. It is the most abundant medusa along the Australian coast, and is often cast up on the beaches in long wind-rows during storms.

A small fish, Trichinurus Jeclivis, is often seen living commensally with the medusa.

Catostylus cruciatus.

Rliizostoma cruciala, LESSON, 1829, Voyage de la Coquille, Zooph., p. 121, planche ll, fig. I. Rharopilus cruciatus, AGASSIZ, L., 1862, Cunt. Nat. Hist. U. S., vol. 4, p. 153. (!) Riiacopilui cyanolobalus, AGASSIZ, L., Ibid., p. 152. After mss. of Couthouy. Crambeua cruciata, HAECKEL, 1880, Syst. dcr Medusen, p. 620.

Bell hemispherical, 120 to 150 mm. in diameter. 8 marginal sense-organs and 48 lappets. 4 large triangular velar and 2 very small ocular lappets in each octant. There are about 32 deep, radial furrows in the exumbrella. Arm-disk as wide as bell-radius. The 8 mouth-arms are 1.5 times as long as bell-radius. The simple, cylindrical, upper part of each arm is short, while the lower part is about 4 times as long and tapers to a point. These lower parts of the mouth-arms are 3-winged in cross-section and thickly covered with frilled mouths.

The medusa is yellowish-white with rose-red gonads and ring-canal, according to Lesson; but according to Agassiz's note from Couthouy's manuscript, the bell is bluish-white with deep-blue marginal lappets and with carmine mouths upon the arms. It should be borne in mind that Crunihfssa mosaica of Australia is sometimes yellowish-white while other individuals are deep cobalt-blue. This yellowish-white is caused by unicellular, commensal plant cells which sometimes infest the medusa.

Found at Santa Catharina Island and at Rio de Janeiro, Brazil.

Catostylus palmipes.

Crambeua palmipes, HAECKEL, 1880, Syst. der Medusen, p. 620.— LI'NEL, 1883, Annals and Mag. Nat. Hist., scr. 5, vol. 12, p. 268.— SCHULTZ, L. S., 1898, Denkschr. Med. Nat. Gcsell., Jena, Bd. 8, p. 453, taf. 33, fig. i; taf. 34, fig. n.

Bell 64 mm. wide, hemispherical. Exumbrella covered with fine granulations. 64 marginal lappets. In each octant 6 quadratic, truncated velar lappets, flanked by 2 oval ocular lappets only halt as large as the velar ones. Mouth-arms thick, somewhat shorter than the bell-radius. The cylindrical, upper shaft of the arm is only about one-sixth as long as the pointed, ^-winged, lower part. These short, upper shafts of the 8 arms are bound one to another along their sides by 8 membranes, leaving only the pyramidal lower parts of the arms free. Neither clubs nor filaments. Subgenital ostia 3 to 4 times as wide as the columns between them. Color (?) Found from northern Australia to Amboina, Malay Archipelago. Most fully described by Schultze.

Lunel, 1893, observes that this medusa is often found commensal with a fish Carncx melampygus.

668 MEDUS.B OF THE WORLD.

A variety of this medusa, in which the webs spanning between the basal parts of the mouth- arms and the arm-disk are not so well developed as in the typical (,'. finliu i [>cs, was found by the U. S. Fisheries Bureau steamer Albatross at a depth of 150 feet in Manila Harbor, Philippine Islands, on January 13, 1908. Bell 56 mm. wide, flatter and more conical than a hemisphere. Exumbrella finely granular without furrows. 64 lappets. 2 small, oval ocular and 6 indis- tinct, rectangular, sometimes cleft, velar lappets in each octant. Arm-disk 35 mm. wide where it arises from subumbrella, and 27 mm. wide at level of origin of 8 mouth-arms. 4 subgenital ostia slightly wider than perradial columns. A unitary cruciform subgenital cavity. Free parts ot upper arms 5.5 mm. long, lower 3-wmged parts of arms 30 mm. long, 19 mm. wide, with- out appendages. Mouths extend to blunt tips ot mouth-arms without naked areas. Canal- system as in C. purpunis. General color in formalin dull ocher-violet, gelatinous substance milky.

Catostylus tagi.

Crambessa tagi, HA ECKEL, 1869, Zintschrift fur wissen. Zool., BJ. 19, p. 509, taf. ;S, }q, 8 fign; 1880, Svst. der Meduscn, p. 621 . — GRENACHER UNO NOLL, 1876, Abhandl. Senckenberg Naturf. Gesell., Frankfurt, Bd. 10, p. 123, taf. 1-7, 17 fign. — GREEF, R., 1881, Zool. Anzeiger, Bd. 4, p. 564.

( ?) Crambessa pictoiiutn, HAECKEL, loc. cit., p. 621 .

Bell hemispherical, 500 mm. wide. Exumbrella covered with dendritically branched ridges which extend upward from the outer, pointed ends ot the lappets toward the apex of the bell. 8 rhopalia, with an ocellus on the aboral side and an exumbrella sensory pit, the floor of the pit covered with radiating, branching furrows. 80 marginal lappets; in each octant 4 pairs of oval, pointed, velar between 2 small, pointed, ocular lappets, not half as wide or as long as the velar lappets. Arm-disk somewhat wider than bell-radius. The 4 subgenital ostia are wider than the columns between them, and there is a unitary subgenital porticus.

The 8 mouth-arms are as long as the bell-diameter. The simple, laterally compressed, upper part of each arm is less than one-third as long as the 3-winged, lower part. These lower parts bear 2 lateral, outwardly projecting wings which are about 60° apart, and a ventral (inner) wing which is 150° from the lateral wings. The wings taper to a point at the lower end ot the mouth-arm. The free edges of the 3 membranous, leaf-like expansions of the arms are complexly folded and bear numerous mouths which are bordered by a row of small ten- tacles. There are neither clubs, filaments, nor other appendages upon the mouth-arms. The circular muscles of the marginal zone ot the subumbrella are interrupted in the 8 principal radii.

The cruciform central stomach gives rise to 16 radial-canals, 8 of which extend to the sense-organs and 8 are intermediate and adradial in position. All are connected by a ring- canal. Centripetal to the ring-canal the 16 radial-canals give oft" an anastomosing network of vessels which fuse with the ring-canal, and on its outer side the ring-canal gives off a net- work which extends into the lappets and fuses with the outer ends of the 16 radial-canals. Each of the 8 principal mouth-arm-canals gives off 3 side branches which extend down the 3 membranous leaves of the arm and send branches off to the mouths. These 3 branches then fuse again with the central canal at lower end of mouth-arm.

The medusa is opalescent yellowish or milky bluish-white, sometimes brown. The dendritic ridges of the exumbrella are reddish or brownish-purple. Gonads yellowish.

This medusa is found in brackish waters near the mouths of rivers from Senegambia, Africa, to France. It is well described and figured by Grenadier and Noll.

"Crambessa pictonum" of Haeckel, from the mouth of the Loire and in le Croisic harbor, France, is closely related to, if not identical with, C. tugi. It is distinguished, according to Haeckel, by the peculiar rectangular elevations separated by furrows upon the exumbrella. These rectangles are not quite as wide as the largest velar lappets and are all of the same size. They are arranged in a 4-sided, cruciform system upon the exumbrella and are separated one from another by deep, parallel furrows. The velar lappets are said to be somewhat wider than they are long, and the mouth-arms are shorter than in C. ttigi. Haeckel found this medusa in August on the southern coast ot Brittany. He states that when the medusa's bell

o J

is 30 mm. wide, the mouth-arms have only a single row of mouth-trills on their ventral sides, as in his genus Huplorluza, and the lateral, leaf-like wings develop later.

RH1ZOSTOM.-E — CATOSTYLUS. 669

Catostylus stublmanni.

itiililnitinrii, CHUN, iS^f>, Mittlu'il. N'jturlii^t'T. Museum, Hamburg, Bd. i *v p. 10, taf. i, 2 ngn.

Bell hemispherical, 80 to 200 mm. wide. 8 marginal sense-organs, set within deep clefts in the bell-margin. 112 marginal lappets. The ocular lappets are short, pointed and small, but the 12 velar lappets in each octant project farther outward and have rounded margins. They are separated one from another by long, deep grooves extending up the sides of the ex- umbrella. Each of these lappets is provided with ;i median longitudinal row of sharp-pointed projections on the exumbrella side. The 8 mouth-arms are hluntlv pointed and are shorter than the bell-diameter. The subgenital ostia are one-thud to one-fourth as wide as the columns between I hem. A unitary, subgenital porticus.

The bell is yellowish-brown or milky-yellow, besprinkled with purple-brown blotches, which are most numerous near the margin. The marginal lappets have rusty-brown, longi- tudinal median streaks. The arms are colorless and the mouths are usually spotted with brownish-purple.

8 specimens found 4 miles above the mouth of Ouilimane River, East Africa, in February and March. Described in detail by Chun, 1896.

This species resembles C. orsini in that the mouths are not developed upon the lower, pointed, knob-shaped ends of the mouth-arms. The outer zone of circular muscles of the subumbrella is interrupted near the margin in the 8 principal radii, but centripetal to this they are unbroken and form a complete annulus.

Catostylus orsini.

Muitigias oriini, YANHUI-M.N, 1888, Bibliothcca Zoologica, Bd. l, Hi-ft. 3, pp. 34, 44. taf. 4, fi^n. 1-4; 1902. Wilson. Hurl'. cli-utsch. Tirfsee Expedition, Dampfcr 1'alJiria, Bd. 3, Lfg. I, pp. 48, 49. — MAAS, 1903, Scyphomcdusen dcr Siboga Expedition, Monog. 11, pp. 63-66.

Umbrella 65 mm. wide, with smooth, exumbrella surface flatly rounded with incurved margin. 8 marginal sense-organs. 144 small, sharp-pointed, marginal lappets. ih velar lappets between 2 somewhat smaller, ocular lappets in each octant. A radial furrow extends up the side of the exumbrella in the line of the cleft between each adjacent pair of lappets. The 8 sense-organs are set within deep niches and there is an exumbrella sensory pit with radiating furrows above each sense-club. The subumbrella displays a deep annular furrow on the inner side of which lies the ring-canal. Centrifugal to this furrow is a zone of power- ful circular muscles, which are not interrupted in the 8 principal radii.

The arm-disk is nearly as wide as the radius of the bell and the 4 arm-disk pillars are wider than the ostia of the subgenital porticus. The simple upper pan of each of the 8 mouth- arms is very short and only one-third as long as the j-winged lower part of the arm. It is also thin and ribbon-like, and in this respect is in marked contrast to the large, 3-cornered lower part of the arm. The upper part of the arm bears no dorsal mouths, but only a single row of fulled mouths along its ventral side. The large, ^-sided, lower part of the arm is elongate, prismatic, with a short gelatinous, pyramidal, bluntly pointed, 3-cornered knob at its end. Altogether the entire mouth-arm is about as long as the bell-radius. The lower part of the arm bears frilled mouths, but neither filaments nor other appendages. The lower end of the arm is naked and devoid of mouths, as in Catostylus stuhlmanni, and forms a blunt, triangular knob which on the outer side is nearly half as long as the upper part of the arm itself, but only one-third of this length on the two radial sides.

8 canals extend down the middle of the 8 mouth-arms and send ramifying branches to the frilled mouths. These 8 arm-canals enter the small, central stomach, from which arise 16 straight radial-canals, 8 ocular and 8 adradial, connected one with another by a wide, circular vessel. An anastomosing network of vessels arises on the inner side of the ring-canal between the radial-canals, although this network does not fuse with the radial-canals them- selves, but arises solely from the ring-canal. The radial-canals are about twice as wide as the ring-canal. The unitary, subgenital porticus is very small. Color (?) Found at Assab, Red Sea, in June.

670 MEDUSAE OF THE WORLD.

Catostylus stiphropterus.

Crambcssa stiphroptrra, SCHULTZE, L. S., 1897, Abhandl. Senckenberg, Naturforsch. Gcscll. Frankfurt a. M., BJ. 14, Heft 2, p. 159, taf. 15, fign. 4, 5, 5<J.

Bell flatly rounded, 100 mm. wide, with a smooth, exumbrella surface which lacks the protuberances found in C. tnostiicus. There are 8 marginal sense-organs. The rhopalar, marginal lappets are slender and sharp-pointed, and in each octant there are at least 5 larger, cleft, velar lappets about 10 mm. long and 6 mm. wide at their bases. The arm-disk is about 38 mm. in diameter, somewhat less in width than the bell-radius. The 4 arm-disk-columns are nearly as wide as the 4 narrow, subgenital ostia. Lower arm 5 times as long as upper, the total length of both not quite equal to that of the bell-radius. Upper arm wholly free, differing in this respect in the number of its marginal lappets and in its narrow subgenital ostia from C. palmipes.

The exumbrella displays 4 perradial areas of indistinct, round, brown spots which do not extend to the bell-margin.

Found at Ternate, Malay Archipelago.

Catostylus viridescens. Crambessa viridescens, CHUN, 1896, Mitthcil. Naturhist. Museum, Hamburg, Jahrg. 13, p. 12, taf. I, fig. 2.

Bell 80 mm. wide, hemispherical. Marginal lappets ( ?) Arm-disk wider than the bell- radius. Subgenital ostia wider than the spaces between them. 8 short mouth-arms, not longer than bell-radius. Upper arm about one-fifth as long as the lower part. Bell sea-green, mouth-arms colorless. Frilled mouths dark-violet. Two specimens found at the mouth of the Pangani River, East Africa, late in November. The marginal lappets were lost in both specimens. Characterized chiefly by its sea-green color.

Catostylus ornatellus.

Loborhiza ornatella, VANHOFFEN, 1888, Bibliotheca Zoologica, Bj. i, Heft. 3, pp. 28, 41, taf. 2, fign. 3-6.

Disk flatly rounded, the gelatinous substance thick. Size ( ?) The exumbrella is finely and evenly granulated, but these granules fuse into rows upon the marginal lappets. 8 mar- ginal sense-organs and 80 marginal lappets. In each octant there are 4 pairs of bluntly pointed, nearly rounded, velar lappets, and 2 very small, sharp-pointed, lancet-shaped ocular lappets. The velar lappets adjacent to the ocular lappets project farther outward and are sharper- pointed than the remaining velar lappets. There is a powerfully developed zone of ring- muscles in the subumbrella, but these are relatively indistinct and somewhat interrupted in the radii of the 8 ocular radial-canals.

The arm-disk is supported by 4 thick arm-pillars, which flare outward at their sub- umbrella bases so as to recall a Maltese cross when viewed looking toward the subumbrella surface. The 4 perradial columns of the arm-disk are about as wide as the 4 genital ostia, but they appear wider than the genital ostia, for their flaring bases curve around in 8 hook- like lateral projections so as to partially close the openings of the genital ostia. The opening of each genital ostium is still further blocked by a triangular pointed flap of the arm-disk which projects over the middle of the ostium, so that each osiium appears as if constricted into 2 side-openings (see figures by Vanhoffen, 1888, taf. 2). The arm-disk is octagonal, and there is a unitary subgenital porticus with 4 folded, U-shaped gonads.

The 4 pairs of mouth-arms are very thick, but only about two-thirds as long as bell- radius. The simple upper half of each arm is short, but the lower half gives rise to 2 dorsal, wall-like lamellz which bear the mouths on their free outer edges. The ventral side of each mouth-arm also gives rise to a similar lamella; and thus the lower parts of the mouth-arms are 3-rayed in cross-section. The 2 dorsal lamellae are set ofF one from another at an angle of about 60°, while the ventral lamella is at an angle of 150° from the 2 dorsal lamellz. The outer edges of these 3 wing-like lamellae fold in and out and give rise to short, lateral branches, along the edges of which the numerous mouths are placed. There are neither filaments nor other appendages among the mouths. The 3 wings of the mouth-arms end in a blunt point at the lower extremity of the mouth-arms.

KIU/."M'o\l.K CATOSTJ I.i 8. (171

The 8 ocular radial-canals are |omed one to another by a thick, irregularly anastomosing, network of canals. The ring-canal is not clearly defined. Other radial-canals (?) Color l ; Found at Puna Island, near Guayaquil, coast of Equador, South America.

Catostylus tripterus.

To\arl\tus tripterus, HAF.CKEL, 1880, Syst. dcr M-'.lusrn, p. 586.

Crambessa iriptera, VANHOFFFN, 1901. WISM-M. F.rt^-b. deutachea Ticfscc Expt-,1. I'tildivia., Bd. 3, Lfg. i, p. 52.

Bell 50 mm. wide, hemispherical. 8 rhopalia, 48 lappets. In each octant 4 wide, nearly quadratic, velar lappets between 2 smaller, but lunger, conspicuously projecting, ocular lappets. 8 arms, somewhat longer than bell-radius, are grouped in 4 pairs, and each consists of a stout, long, nearly cylindrical upper part of the arm which is twice as long as the ^-cornered pyramidal, lower part ol the arm. There are 3 wide, leat-hke projections on this lower part of the arm, and the mouths on their edges are only slightly folded. There are no appendages between the mouths. 4 horseshoe-shaped gonads.

Found on the west coast ot tropical Africa at Fernando Po Island, on the coast of Guinea. Color (?)

Catostylus turgescens. Toxoclytus lurgticens, SCHULTZE, L. S., 1898, Dcnkschr. McJ. Nat. Gcs,. Jena., Bd. 8, p. 455, uf. ',4, figs, i*,, 14.

This is described by Schultze from a single specimen which appears to be quite abnormal — so much so that I have but little taith in its value.

Bell flatly rounded, 90 mm. wide. Exumbrella smooth. 9 marginal sense-organs. Marginal lappets narrow and sharp-pointed. Number ( ? ) Arrangement ( : I 6 subgemtal ostia wider than the arm-shafts which separate them. Arm-disk flat. The 6 upper arms are thick, arrowhead-shaped and curve outward; they are about 19 mm. long and 17 mm. wide. Lower arm sharply pointed, only about 12 mm. long. There are thin filaments upon the arm-disk between the mouths, but no other appendages. The canal-system consists of a fine anastomosing network on the inner and outer sides of the ring-canal. This network does

o o

not reach the margin. There are also unbranched radial-canals and blindly-ending centrip- etal canals. Amboina, Moluccas. Color (?)

%

Catostylus purpurus, sp. nov.

This torm is closely related to Catostylus stiphropterus, from Ternate, but differs in the number and arrangement ot its marginal lappets and in its deep, uniform dark brownish- purple colorarion.

Disk flatter than a hemisphere, 88 to 115 mm. wide, 26 to 35 mm. high. F'.xumbiella smooth. 8 rhopalia flanked bv short, narrow, bluntly rounded lappets. A furrowed exumbrella sensory pit above each rhopahum Rhopalar lappets somewhat narrower than the velar. In each octant there are 4 cleft and 2 simple velar lappets arranged in a detinue manner, see A and it, tig. 412. In the middle of each octant there area pair of cleft velar lappets, and these are flanked on their outer sides by 2 simple velar lappets, which are in turn bordered by 2 cleft velar lappe's. Thus the lappets ot each octant are arranged in sequence as fol- lows: (l) a small, simple, rhopalar lappet adjacent to the sensory-club; (2) a cleft vcl.n lappet; I}) a simple velar lappet; (4 and 5) 2 cleft velar lappets; (6) a simple velar lappet; (7) a cleft velar lappet; iS) a small rhopalar lappet. Thus the bell-margin displays <>'> nearly equally spaced notches, there being 16 rhopalar and So velar terminal lappets.

The arm-disk is about as wide as the bell-radius at its origin from the subumbrella, but at the level of the origins of the 8 mouth-arms it is somewhat less than three-eighths as wide as the bell-radius. There are 4 long, narrow, genital ostia nearly as wide as the 4 perradial columns of the arm-disk. Each ostium is constricted bv a thick, wide, median gelatinous projection from the arm-disk. A long, finger-shaped papilla arises from the subumbrella surface in the median line on the outer side of and close to the opening of each genital ostium, and this is in some specimens flanked by a pair ot cocks-comb shaped, gelatinous projections from the floor of the subumbrella as is shown in c in text-figure 412. I he arm- disk is notched in each perradius. The unitary subgenital cavity is wide and cruciform.

672

MEDUS/E OF THK WORLD.

There are 8 separate mouth-arms, each three-eighths as long as the bell-diameter. The lower, 3-winged, expanded part of each arm is about 5 times as long as the simple, flattened, upper part of the arm. Each mouth-arm is bluntly pointed and us frilled mouths lack fila- ments or other appendages. The mouth-frills extend to the extreme tip of the arm and there is no naked, terminal portion.

A zone of powerfully developed, unbroken, circular, subumbrella muscles extends from the outer edge of the arm-disk to the bell-margin. The gelatinous substance of the bell is very tough and of a leathery consistency.

16 radial-canals leave the central stomach: 8 rhopalar and 8 adradial. These are con- nected by a ring-canal on the outer side of which there is a fine-meshed and on the inner side a coarse-meshed network of anastomosing vessels.

The medusa is dull, uniform dark brownish-purple, resembling old leather soaked in water. It is abundant in Manila Bay, Philippine Islands, where it occurs over the bottom in shallow water.

Seven specimens found in Manila Bay on December 9, 1907, are in the collection made by the U. S. Fisheries Bureau steamer Albatross, and a larger one on March II, 1908. This largest specimen serves as the type of the species in the National Museum at Washington. Its dimensions in mm. are as follows: Bell 1 15 wide, evenly rounded, 35 high; arm-disk 75 wide where it arises from the subumbrella, 52 wide at level of origin of mouth-arms; mouth-arms 58 long, upper arm / long, lower arm 51 long and 30 wide.

FIG. 412. — Catost\lus purpurus, sp. nov. Drawn by the author, from specimens obtained by the U. S. Bureau of

Fisheries steamer Albatross in Manila Harbor. A, oral view, half natural size. Only two of the mouth-arms are shown; $ others are cut off close to their points

of origin, and one is shown cut across in its expanded 3-winged part. B, side view. C, genital ostiuin

showing subumbrella papilla flanked by a pair of cocks-comb-shaped subumbrella projections. D,

exumbrella view of rhopalium showing furrowed sensory pit.

Genus LYCHNORHIZA Haeckel, 1880.

7,v lin(jrlii?a+ Cramborhiza, HAECKEL, 1 880, Syst. der Medusen, pp. 587, 633. — VANHOFFEN, 1888, Bibliotheca Zoologtca, Bd. I ,

Heft. 3, pp. 28, 41 . Lycl:norhisa,MfLAS, 1903, Scyphomedusen der Siboga Exped., Monog. 1 1, pp. 48, 80; 1906, Revue Suisse de Zool., tome 14, p. 102.

The type species is Lychnorhiza lucerna Haeckel, from the coast of Brazil, Rio de Janeiro to Pernambuco.

GENERIC CHARACTERS.

Rhizostomata triptera with filaments, but without clubs, upon the 3-winged mouth-arms. No axial terminal club at the end of each arm, and no club-shaped appendages between the mouths. The stomach gives rise to 16 radial-canals : 8 rhopalar and 8 adradial. The rhopalar canals extend to the bell-margin, but the adradial ones end in the ring-canal. Blindly ending centripetal vessels arise from the inner side of the ring-canal and may anastomose to some extent. On its outer side the ring-canal gives off a network of anastomosing vessels which extend into the lappets.

lilll/.iis-liiM.K I.VCIINOUMIZA. (>7'.i

Among characters of minor importance the circular muscles of the subumbrella are entire anil not broken in the 8 principal radii. The sense-clubs have each a sensory pit with radiating furrows over its floor. The subgenital ostia are wider than the columns between them.

This genus is so closely allied to Crambtoni that the iwo might readily be merged. It may. however, be distinguished by having no club-like appendaiu-s beiween the mouth-frills.

Lychnorhiza lucerna Haeckel.

/. \- hri',r ltr:,i lu< -r-r titi. H A t > KM., iSSo. S\ ^i. ilcr M< hi r ii, p. 1587, taf. 34, 8 fign. H \M\NS. I XX i . |"Ln.i. 7,eit. fur Naturw., B,i. I ^,

p. 249 (anatomy of mouth-arms).

('runiftfirliizu ftagellata (voung nu-ilusa), HAKCKH-, Ibid., p. 646. Lychnorhiza flagellalu, \' AMIUI ? i \, I SSS, Hibliutlirt .1 /,. n ilu'n i. IM. I , Hrft ', , pp. 2<$, 42, laf. 2, fig. 7; taf. 3, fign. 1-3.

The bell is flatter than a hemisphere, 120 to 150 mm. in diameter, and its exumhrella surface is besprinkled with fine granules and minute, sharp-pointed projections. There are 8 marginal sense-organs and 48 marginal lappets. The 16 lappets flanking the 8 marginal sense-organs are small, sharply pointed, and triangular, while the 4 velar lappets of each octant are 3 times as broad and 3 to 4 times as long as those flanking the sense-organs. These velar lappets are more nearly oval in outline and not quite so sharply pointed as are the ocular. The 8 stout, adradial mouth-arms arise from a large, gelatinous base which projects from the center of subumbrella. These 8 mouth-arms are laterally compressed, separate one from another, and about as long as the bell-diameter. The outer sides of the upper halves ot the mouth-arms are smooth and bear no mouths, but below this the arm is developed into a ventral median and 2 large lateral wing-like membranes, all 3 of which meet at a point below. The edges of these 3 membranes are much folded and are lined by numerous mouths which are surrounded by minute, clubbed tentacles. In addition, the edges adjacent to the mouths bear numerous long filaments, 120 to 160 upon each mouth-arm. Near their bases these filaments are conical, but they expand beyond into a ribbon-like shape, each of the narrow edges of the ribbon being lined by a row of small, club-like nematocyst-organs. Each mouth- arm bears a pair of very long filaments and 15 to 2O somewhat shorter filaments, the remainder being still shorter. The longest filaments exceed the length ot the mouth-arms themselves.

There is a well-developed, unbroken zone ot circular muscles in the outer part of the subumbrella. The central stomach is cross-shaped, the arms ot the cross being m the diameters of the principal radii, while the 4 subgenital pits lie in intermediate positions. 16 radial- canals extend out from the central stomach: 4 in the principal radii. 4 in the secondary, and 8 in the tertiary fadradial) radii. The 8 principal radial-canals extend to the sense-organs, but the 8 adradial ones end in the ring-canal, which is at some distance inward from the margin. The ring-canal gives off 32 blindly-ending, centripetal vessels, 2 beiween each pair of radial-canals. On its outer side the circular vessel gives rise to about 160 radiating vessels (20 in each octant) which extend into the lappets and are connected by numerous, anas' omosing vessels formin» a marginal network. Each of the 8 mouth-arms sends a canal into the central

f~> o

stomach. This mam canal of each mouth-arm gives rise to 2 side branches, each ot which extends down a lateral wing of the mouth-arm under the mouths, while the central canal extends down the center of the lower side of the mouth-arm. The gonads are much-folded membranes lining the inner walls of the 4 subgenital pits. They fill the greater part ot the stomach cavity and according to Haeckel, they pro|ect outward through the subgenital pits. This is, however, unknown in any other rhi/.ostomous medusa and is. 1 believe, merelv a result of shrinkage, etc., in the preservative fluid.

Haeckel studied a single specimen of this medusa from Rio de Janeiro, Brazil. He gives a detailed description accompanied by figures.

I am inclined to believe that " /.. flagellata" is only the young ot /,. lucerna. In order the more readily to aid future students in settling this question, we present a detailed description of " L. jiiiH,-ll<it<i:" The disk is 80 mm. \\idc, about 30 mm. high, and evenly lounded. It is very tough with thick gelatinous walls. The exumbrella is covered with fine granules, which become larger near the marginal lappets and set themselves in elongate lines over the lappets. There are 8 marginal sense-organs and 48 marginal lappets. In each octant 4 large, bluntly triangular, velar lappets between 2 very small, sharp-pointed, lancet-shaped, ocular lappets

674

MEDUSAE OF THK WORLD.

which are hardly half as long and one-fifth as wide as the velar lappets. The marginal sense- organs are similar to those ot Catostylus. The ring-muscles of the subumbrella are very powerfully developed, but are partially interrupted over the 8 ocular radial-canals. The arm- disk is about as wide as the radius of the umbrella. It is 8-sided, the narrow sides being in the radii of the arm-pillars; and the wide sid'es, which are 3 times as wide as the others, are in the radii of the 4 subgenital ostia. The subgemtal ostia are thus 3 times as wide as the arm- pillars between them.

8 thick mouth-arms arise from the arm-disk, and these are about as long as the bell- radius. The lower part of the arm is somewhat longer than the upper. There are 2 well- developed, thick, dorsal mouth-lamellae or "wings" which project from the lower arm and these fuse with the ventral mouth-lamella at the pointed end of the arm. The ventral side of the mouth-arm is complexly folded and gives rise to lateral lappets. The filaments, which arise at the ends of these lappets between the mouths, are shorter than in the mature L. lucerna. The 4 sides of the genital organs are bent at right angles, thus forming a cross of 4 right- angled membranes which are very much folded. The gastrogenital cavity and subgenital porticus are small and much reduced.

16 radial-canals (8 ocular and 8 interocular) emerge from the cruciform, central stomach. These 16 radial-canals are put into connection one with another by a wide ring-canal which is about half-way between the center and the margin. Peripheral to this ring-canal there is a network of vessels, although the 8 ocular canals run through and fuse with this network. 32 blindly-ending, centripetal vessels extend inward from the ring-canal toward the center of the disk, but they end blindly before reaching the edges of the stomach. There are 2 of these blindly-ending diverticula between each successive pair of radial-canals, and in some cases they fuse one with another. Color (?)

Found at Pernambuco and at Contigeriba on the coast of Brazil. The most complete description is that of Vanhoffen, 1888, from which the above has been mainly derived.

I am inclined to believe that this medusa will prove to be only a young stage of Lvcli- norhiza lucerna Haeckel. The marginal lappets, mouth-arms, and canal-system are similar in both. According to Haeckel the bell is flatter and thinner in L. lucerna than in L. flagellata; also in the mature L. lucerna the gonads protrude through the subgemtal ostia, but this may be due to defects in preservation or to the general breaking up of these organs which commonly occurs in medusae when the genital products are set free. Vanhoffen did not compare his specimen of L. flagt-Ilatn with Haeckel's type in the Berlin Museum. The only distinguishing features according to the accounts ot Haeckel and Vanhoffen are as follows:

Lychnorhiza lucerna:	Lvchnorhiza flaaellata:
Disk, flat, gelatinous substance thin. Umbrella 120 to 150 mm. wide.	Disk nearly hemispherical, gelatinous substance thick. Umbrella 80 mm. wide ?*
Mouth-arms are twice as long as the radius of the umbrella.	Mouth-arms arc only a little longer than the ra- dius of the umbrella.
Mouth-arm filaments longer than the mouth-arms.	Mouth-arm filaments very short (broken off:).
4 separate, subgenital cavities. Gonads protrusive.	Subgenital porticus present. Gonads do not pro- trude through the subgenital ostia.

*Vanhoffen docs not state the size of his specimen.

The presence of a unitary subgenital porticus in " L. fla^cllata" is its only really distinctive character, but this is often highly variable in development in different specimens ot the same medusa. See Maas, 1903, Scyphomedusen Siboga Exped., p. 36.

Lychnorhiza bartschi, sp. nov.

Named in honor of Dr. Paul Bartsch to whose care and skill the excellent preservation of the medusae upon the Philippine expedition ot the Albatross is due.

Bell 74 mm. wide, flatter than a hemisphere and with smooth exumbrella surface. Gelat- inous substance thick but not very rigid. 8 rhopalia, each with an ocellus and an exumbrella

HIIlXdSToM.K — LYCHXulUH/ \.

I -,7.'i

sensory pit with dendritic furrows over its floor. 96 (8X12) lappets, 10 liluntlv pointed velar lappets between 2 somewhat smaller ocular lappets in each octant. Arm-disk 4<S mm. wide where it arises from the suhumhrella, hut onlv 40 mm. wide at the level of origin of the X mouth- arms. The 4 subgenital ostia (sgo) are crescent-shaped and each is covered above by a gelatinous flap. They are only half as wide as the perradial columns between them. Kadi perradial column exhibits a niche, n, figs. 413 and 414, on its outer side which hears a super- ficial resemblance to the subgenital ostia. The subgenital cavity is unitary. t

The 8 mouth-arms are laterally compressed and 36 mm. long, the lower ^-winged parts ol the arms being 24 long and 2} wide. Numerous simple, laterally flattened, tapering filaments arise from between the frilled mouths on all sides of the mouth-arms and fioin the arm-disk. The filaments upon the arm-disk are about 30 mm. long, but those from the outer pans ot the mouth-arms are shorter.

The central stomach is cruciform and about 40 mm. wide. 16 simple radial-canals, S rhopalar and 8 adradial. These are all put into intercommunication with a wide ring-canal which is at some distance inward from the margin. The adradial canals terminate in this ring-canal, but the rhopalar canals extend onward to the sense-organs. On its inner side the

4'3-

4'4-

Vi<;. m.—T.vrlinorhisakartsclii. Drawn by the author. A, Oral view. B, sense-organ seen from exumbrrlh tide. l-'n;. 414.— Lwhnorhiza barlschi, sp. nov. Natural size, drawn by the author, sgo, subgenital ostium. n, niche in i column of arm-Jisk.

ring-canal gives rise to ift blindly ending networks of vessels which do not connect either with the stomach or with the radial-canals. On its outer side a fine-meshed network of vessels arises from the ring-canal and fuses with the rhopalar vessels. Around the margin at the bases of the lappets there is a marginal ring-canal of fine caliber. There is a unitary uninterrupted system of ring-muscles in the marginal zone of the subumbrella. but there are no radial muscles.

The gelatinous substance is translucent and milky in formalin, and the gonads, mouth- frills, and canal-system are milk\ -\ ellow. I am told by Dr. Bartsch that these colors in tin- living animal were nearly as they appear in the formalin specimen.

\ single specimen was found bv the U. S. Fisheries Bureau steam, i. ll'-.itross, at Jolo Anchorage, Philippine Islands, on February 13, 1908 (text-figs. 413 and 414'

676 MEDUSAE OF THE WORLD.

Genus CRAMBIONE Maas, 1903.

Crambione, MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. II, pp. 48,81; 1906, Revue Suisse de Zool.,tome 14, p. 103.

The type species is Crambione mastigofhora, Maas, from the Malay Archipelago.

GENERIC CHARACTERS.

R/uzostomata tnptera in which each mouth-arm is 3-wmged and the wings bear secondary branches. All 3 of these wing-like expansions and their branches bear mouths, among which there are clubs and filaments. No terminal club at the end of each arm. With a unitary, sub- genital porticus and with 4 slit-like, subgenital ostia.

The canal-system consists of 8 vessels which extend outward to the bell-margin in the perradii and inteiradii, and 8 adradial canals which end in the ring-canal at some distance inward from the bell-margin. On the outer side of the ring-canal is a network of vessels, and on the inner side the ring-canal gives off a network between each 2 radial-canals, which does not connect with the radial-canals themselves. The circular muscles are unitary, being unbroken by radial strands. The marginal sense-organs have a pair of eye-spots and a sensory pit with large radial furrows.

This genus is closely related to Catostylus, but is distinguished by having clubs and fila- ments upon its mouth-arms, these being absent in Catostylus. It is also very closely allied to Lychnorhiza, but has both clubs and filaments upon its mouth-arms, whereas Lychnorhiza has filaments only.

Crambione mastigophora Maas.

Crambione mastigophora, MAAS, O., 1903, Scyphomeduscn der Siboga Expedition, Monog. 1 1, p. 49, taf. 6, fign. 47-53; taf. 8, figs. 71-74; taf. II, fign. loo, 104; taf. 12, fig. 113; 1906, Revue Suisse de Zool., tome 14, p. lov

The bell may become 400 mm. wide and is highly arched and rounded. The gelatinous substance of the center is thick, while the margin is sharply set off from the center and is thin-edged. The exumbrella is smooth. There are 8 marginal sense-organs. These sense- clubs have each a bulbular swelling on the subumbrella side and 2 lateral ocelli near the outer

O

end of the club. There is also an entodermal hthocyst mass. There is a large, heart-shaped sensory pit on the exumbrella side above each sense-organ, and prominent radiating furrows spread out from the center ot the pit-cavity just above the base of the sense-club. 2 small, pointed, lanceolate, ocular lappets flank each of the 8 sense-organs, and in each octant are also 8 to 10 velar lappets which are elongate, with rounded outer edges and deep clefts between them, and which increase in number with age.

The arm-disk is very wide and 8-sided. The 4 interradial, subgenital ostia are narrow, elongate, and slit-like, but not as long as the arm pillars between them. 4 perradial, slit-like depressions or fossae in the arm-disk are somewhat higher than the subgenital ostia to which they bear a close superficial resemblance; they are not to be confused with subgenital ostia, however, for they are mere depressions in the surface of the arm-disk. The 8 adradial mouth- arms alternate in position with the subgenital ostia and the perradial fossae. In the young medusa they are grouped in 4 pairs, but in the adult they arise at equal intervals from the sides of the arm-disk. Basal pans of mouth-arms massive, nearly circular in cross-section; in their lower halves each gives rise to 3 projecting, lateral expansions or "wings " which meet at the lower end of each arm, giving a pyramidal general outline to the outer half of each mouth- arm. There are numerous mouths along the lower inner lamella ot each mouth-arm and along the edges of the 2 lateral wings, as in Catostylns. But unlike Catost\lus many small, club-shaped and some long, tapering, filamentous appendages arise from both the lower and upper sides of the mouth-arms between the mouths.

The central stomach is cruciform, the axes of the cross being in the perradii . 4 perradial, 4 interradial, and 8 adradial canals arise from the stomach. The perradial and interradial canals extend to the bell-margin, but the 8 adradial vessels end in the ring-canal, which lies some distance inward from the margin of the bell. On its outer side the ring-canal gives off a neiwork of vessels which anastomose with the perradial and interradial canals. Centrip- etal to the ring-canal and arising from it, between the 16 radial-canals, are 16 open networks of vessels. The ring-canal and the 16 radial-canals are of uniform and moderate width.

O

The peripheral network of vessels is of finer caliber and the 16 networks on the inner side of the ring-canal are of wider caliber than the outer network, but not as wide as the radiating vessels. These inner networks do not fuse with the radial-canals.

RHIZOSTOM.E— CKAMlUdVK, MA.STICI As. (177

The 4 imerradial gonads form a cross following the lines of the cruciform stomach of the medusa but interior to the border. The adjacent gonads lie so close one to another that the genital cross is extremely narrow and elongate. There is a unitary, subgenital porticus or chamber which serves as a brood-sac for the planula larvae. There is a well-developed, peripheral ring-muscle in the subumbrella, and this is not broken by radial muscle-strands, such as are found in Mastigias.

The gelatinous substance is translucent and milky. The frilled mouths are whitish and the clubs reddish. The gonads are flesh-colored, pinkish, or reddish.

This medusa is found at Amboina and at other places among the islands of the Malay Archipelago. It is described and figured in detail by Maas, 1903.

Crambione cookii, sp. nov. Plate 74, fig. 2.

Bell hemispherical, 110 mm. wide, gelatinous substance tough. Fxumbrella smooth in the flexible zone above the margin, but the inflexible central part of the dome is reticulated by a network ot deep furrows trending more or less radially outward from the apex. 8 rho- palia. 88 large, pointed, marginal lappets, equal in size each to each. Mouth-arms 1.5 times as long as bell-radius. The lower two-thirds of each arm is 3-winged and the outer edges of these lamellae are complexly folded and hear the mouths. 4 slender, uniform filaments, as long as the bell-radius, arise from the arm-disk. There are about z to 6 globular, gelatinous appendages on the outer sides of each mouth-arm. These are about 6 mm. long.

The gelatinous substance of the bell is opaque, horny, milky-yellow. The marginal ring-muscles ot the subumbrella are brown and the valleys of the exumbrella furrows are of a lighter shade of the same color. Mouth-arms and vesicles translucent milky-blue. Mouth- trills brown.

Found by me on the surface along Great Barrier Reef, off'Cookt own, Queensland, Australia. May 4, 1896, during Dr. Alexander Agassiz's exploration of the reefs. Named in honor of the distinguished navigator. Captain James Cook, whose voyage first made the (Queensland coast known to the world, and whose ship, the Endeavour, met with misfortune in June, 1770, near the place wherein this medusa was found.

Genus MASTIGIAS L. Agassiz, 1862.

Alastigias, A<;ASM/, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152. — Cuvfs, 1883, Organisation und Ent'.u. 1.. di ' Mi'.ln-.-n.

p. 61.— VON LENDENFELD, 1884, Proc. Linncan Soc. New South Wali-s, vol. 9, p. 300.— KIMIIX»C 1 1 , 1895, Zoological

M.ig. Tokyo, vol. 7, No. 78. — CHUN, 1896, Mittheil, Nat. Mus. in Hamburg, Jalirg. i-,, p. i-,. \l\^, H,O.J, Ahli.mdl.

Akad. \Vi>-,rn., Munclu-n, Suppl. Bd. i, Abli.indl. S, p. 46. Mastigias + F.ucrambessa, HAECKHI., 1880, Syst. d.-r Mnluven, pp. 622, 624. Mastigias+ De smostoma, VANBOFPCK, iSSS, Bihhotbi-ca Zoologica, Bd. 1, Hrft. 3, pp. 33, 35, 44, 41;. — MAAS, l<jo;. So pli.mu--

dusen dcr Siboga Exped., Monog. II, pp. 62, 66, 81. M,nt\'£ias, VANHOFFEN, 1902, Wisscn. Ergeb. dcutsch. Ticfscc ExpL-.l., I'alJii'ia, Rd. 3, I.fi>. i, p. 46.

The type species is the widely distributed M. fnipiiti of the Indo-Pacific region. It was first described as Cfplifu papua by Lesson, 1829.

GENERIC CHARACTERS.

Rhizostoinniti triptt-ni with ^-winged mouth-arms which terminate in a naked, club- shaped extremity. There are also smaller clubs and filaments between the frilled mouths. The mouths are developed not only along the edges ot the } leat-like wings of the lower parts ot the mouth-arms, but also over parts ot their flat, expanded sides. The central stomach gives rise to 8 rhopalar canals and numerous, interocular radial-canals all of which anastomose and finally connect with the ring-canal. The rhopalar canals extend straight to the sense- clubs, but the inter-rhopalar canals end in the ring-canal. On its outer side the rinjj-canal gives off a network of vessels which extend into the lappet-zone and fuse with the outer ends ot the rhopalar canals. The ring-muscles ot the subumbrella are interrupted in the 8 rhopalar radii. A unitary subgenital porticus. No furrows in the exumbrella scnsorv pits.

The genus Desmostonia ot \ anhofFen, 1888, conforms in all respects to Agassiz's .! except that there are clusters of filaments upon iis arm-disk at the bases of the mouth-amis, whereas the other species of Mnstig ias lack filaments and have only small clubs on the sides

678

MEDUS.E OF THE WORLD.

of the mouth-arms in addition to the terminal club, I have merged it with Mastigias for the genera among R/uzostotnata triptera are already too numerous, and are distinguished upon differences of such slight imponance that the distinctions threaten to confuse rather than u> clarify the system of classification.

Mastigias is closely allied to Pscudorhiza, but may be distinguished by its numerous, complete, interocular radial-canals; whereas the converging vessels on the inner side of the ring-canal between the 16 radial-canals in Pseudorhiza end blindly without reaching the stomach.

The canal-system of von Lendenteld's Ph \llor hi%a puiifttita is similar to that of Mastigias, but the mouth-arms bear numerous very long filaments without any definite terminal club.

The following synopsis of the forms of Alastioias may be of service, r is the length of the radius of the exumbrella.

Tabular Synopsis of the Forms of Mastigias.

	M. papua.	M. papua var. siderea.	M. papua var. siboga?.	M. ocellata.	M. pantherina.	M. gracile.
Number of	8X8. Rounded.	8X8. Rounded.	9X8. Rectangu-	6x8 or 12X8	16X8. Rectan-	5X8 or 10X8.
velar lappets.			lar.	truncated. Rec-	gular.
				tangular.
Length of	r	2 r	r	r	2 r	— r
mouth-arms.
Length of ter-	2 r	r	2 r	r	4 to 6r	One-sixth r.
minal clubs.
Color.	Bell blue, greenish.	Bell blue, greenish.	Bell yellow ( ?)	Bell reddish-	Bell brown	?
	olive, or brown;	olive or brown;	with orange ( ?)	brown with ring-	with darker
	with white,	with white,	spots. Canals	like spots of white	margin.
	brown, or yellow-	brown, or yellow-	and clubs violet	and brown.	White spots
	ish spots.	ish spots.	to rose-colored.		ringed with
					black.
Where found	Fiji Islands,	Zanzibar, East	Malay Archi-	Indian Ocean,	Samoa.	Red Sea. Dis-
and remarks.	Japan, Malay	Africa.	pelago.	Hongkong,		tinguished by
	Archipelago.			Cocos Islands.		long filaments
	Indian Ocean.					on arm-disk.

Mastigias papua L. Agassiz.

Cepliea papua, LESSON, 1829, Voyage de la Coquille, Zooph., p. 122, planche 11, figs. 2, 3.

Cephta papuensis, GRIFFITH, 1832, Cuvier's Animal Kingdom, plate 3, fig. 3.

Mastigias papua, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152. — HAECKEL, 1880, Syst. der Medusen, p. 623. — MAAS,

1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, pp. 66, 69, taf. 7, fign. 60, 62, 63; taf. 12, fig. 1 1 1 . Psfudorhiza thocambaut, AGASSIZ, A., and MAYER, 1899, Bull. Museum. Comp. Zool. at Harvard College, vol. 32, p. 173, plate

13, figs. 40-44 (young stages). Maslygias papua, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Valdivia, Bd. 3, Lfg. i, p. 47, taf. 4, fign.

17-19. Masttgtas physophora, KISHINOUYE, 1895, Zoolog. Magazine, Tokyo, vol. 7, No. 78, 3 pp., plate 13, figs. 1-13. — SCHULTZE, L. S.,

1898, Denkschr. Med. Nat. Gesell. Jena, Bd. 8, p. 443.

Mastigias physophora, VANHOFFEN, 1902, Wissen. Ergeb. deutsch. Tiefsee Expedition, Dampfer Valdivia, Bd. 3, Lfg. I, p. 49. Mastigias papua var. ph\sophora, MAAS, 1909, Abhandl. Akad. Wissen. Miinchen, Suppl. Bd. I, Abhandl. 8, p. 46.

Bell 30 to 80 mm. wide, usually hemispherical, sometimes flatter and sometimes fuller than a hemisphere. Gelatinous substance firm. Exumbrella surface with very fine granu- lations. 8 rhopalia, each with a pigmented mass of crystalline concretions and a shallow, exumbrella, sensory pit without furrows. 80 marginal lappets. In each octant 2 small, pointed, ocular and 8 larger, rounded velar lappets with deep furrows between them extending a short distance up the sides of the exumbrella. Arm-disk somewhat wider than bell-radius. The 4 subgenital ostia are about twice as wide as the columns between them and are each somewhat constricted in the middle. Subgenital porticus unitary. 8 mouth-arms, each about as long as bell-radius. The simple upper part 1.5 times as long as the 3-winged lower portion of the arm. The frilled mouths are developed not only along the edges of the 3 wings, but also for some distance inward along the sides of each leaf. Each mouth-arm usually terminates at its lower end in a club-like filament which may be as long as the diameter of the bell, but is sometimes reduced in size or even wholly absent. This club is triangular in cross-section and contains an axial canal. A large number of small, club-shaped vesicles arise from between

!{III7.(iST(iM.K - MASTICI VS.

f>79

the mouths on the outer sides of the mouth-arms. The central canal of each mouth-arm gives otTj side branches which lead to the ^ lows of frilled mouths of the winged, lower pan of Un- arm. All 3 of these canals fuse again with the axial-canal at the base ol the terminal club and extend onward as the axial-canal of the club.

The central stomach is cruciform and gives oft S siiaight radial-canals which extend to the sense-organs. These canals are all connected by a wide ring-canal in a zone at a consider- able distance inward from the margin. About ~ to 9 anastomosing radial-canals arise horn the stomach in each octant between the rhopalar canals and fuse with the ring-canal. On its outer side the ring-canal gives off" a fine-meshed net\\oik o| anastomosing vessels winch extend into the lappets and fuse with the outer ends of the 8 rhopalar canals. 1 he circular muscles ot the marginal zone of the subumbrella are widely interrupted in the 8 principal (rhopalar) radii. The gonads are 4 folded walls tormm<; cruciform sides of the subgemtal porticus.

Color quite variable. Bell and motnh-arms usually greenish-blue, or olive-green to olive-brown, and there are a number of yellow, white, or occasionally brown, blue, or green oval spots over the exumbrella, especially near the mar»in. The trills ot the mouths may be olive, greenish-blue, yellowish-green, or brown. The 8 rhopalar radial-canals are darker. This medusa is widely distributed over the Malay Archipelago, Indian ( )cean, and China Sea to Japan, and outward over the Pacific to the Fi|i Islands.

Agassiz and Mayer found an ephyra ot the medusa in Suva Harbor, l'i|i Islands, in Jan- uary, 1898. It was 5 mm. in diameter and quite Hat and disk-shaped. There weie 8 marginal sense-organs. The central mass of dark-brown entodermal pigment granules of the sense-organ was developed, but the peripheral shell of transparent granules hail not \et made its appear- ance. There were 24 marginal lappets, the 16 ocular lappets being about twice as long as the 8 velar lappets. There were 16 radial-pouches from the stomach, ot' which 8 went to the sense- organs and 8 to the velar lappets. I he sub- genital porticus was already unitary and the brachial disk was suspended from the Hu"i ..I the subumbrella by means of 4 gelatinous pillars, exactly as in the adult. The ephyra possessed only a simple, central mouth opening, having 4 cruciform lips. The margins of the lips were lined with a row of short, slender tentacles with knob-like ends exactly like those that sur- round the mouths on the mouth-arms ot the adult medusa. No trace ot the genital organs could be detected, but the gastric cini \\eie represented by 12 short filaments \ \ in each

FIG. 415. — \fasti%ias paplttl, after VanliutTrn, in I'tilJii-i.i Kvprilition.

quadrant). The color of the ephyra was very similar to that of the adult. The ring-canal had not yet begun to develop.

M<i>tii;i,i> [><if>ii<i swims very rapidly by an incessant contraction and expansion of the bell-rim. Being an abundant and variable form, it has given use to main ne.nlv related varieties, such as AI. fxipun var. .s/Aoiy of the Malav Archipcla<;u and \l . ,v/./<n<; ot the east coast of Africa. M. physophora Kishinouvc is another variety found abundantly off the coasts of Shima and Sagami, Japan, during summer and autumn. Its bell is at least 100 mm. in diameter and is light-brown with numerous, round, dark-brown spots near the margin.

Schultze finds this medusa at Amboina. Moluccas, in January and r'ehruan. and it is evidently only a large, dark-colored variety of M . /<<i/>ini. Kishinouvc gi\es an excellent series ot drawings of this medusa.

o

Mastigias papua var. siderea.

Manilas sidcrca, CHUN, 1896, Jahrb. \Vi-rn. V : .Iniri;, Jaliri;. 15, p. 15. taf. i, i

Mastigias, sp., (young medusa >. Si m i I/R, 1898, Abh.m.'l. Senckenberg, Getell., BJ. 14, H«-li. :. p. iM, t..f. i ,-. •

jl/wygKii udtrea, VANBOFFIN, 1901, Wissen. Ergeb. deutseh. Tiefiee Exped., Dam] ! ;. I, p. 49.

{f)Mastigias sidtrc.i. Simir/t. I.. S., 1898, Abliaiull. S,-m Unh.-ri;. C.-rll. \alurl.. H.I. ;4. p. ll.i. taf. i;. :

( ') Eurrambrssa mulleri, HAM KH , iSSo, Sy«t. ,li-r M< !ii CD, p. 614.

1 I \t.iit\£iai mulleri, Visiiuii i -. , 1902, \Visst-n. Kri;cli. I'aliiiria H\pi-il., H.I. ',, I.fi;- I., p. 49.

Bell Hath rounded, 70 mm. wide. 8 marginal sense-organs and So marginal lappets. Ocular lappets narrow, but the 8 intermediate lappets in each octant are semicircular in outline.

680 MEDUS.E OF THE WORLD.

Arm-disk wider than bell-radius, and the subgenital ostia are twice as wide as the radial supports between them. 8 wide, ocular radial-canals and 7 anastomosing, radial vessels in each octant. Mouth-arms are twice as long as bell-radius, the simple upper part of the arm being somewhat shorter than the lower, 3-winged part. Each arm terminates in a single club as long as the bell-radius.

Bell light yellowish-brown with round white spots, which are largest over the ring-canal and smaller near the margin, where they are arranged in 3 or 4 radiating rows between each successive pair of marginal sense-organs. 8 blackish streaks along the 8 ocular radial-canals on the subumbrella, and also white specks in each octant of the subumbrella between the stomach-pouches and the circular furrow. Arms brown with small white spots. Filaments yellowish.

Found along the Zanzibar coast, East Africa, in August and September, and in the western parts of the Indian Ocean.

Chun, 1896, gives a detailed description of the adult and the young of this species.

Haeckel's Eucrambessa miillen from Madagascar is probably identical with this species, but is so imperfectly described that we will never be able to determine it with certainty.

Mastigias papua var. sibogae Maas.

Mastigias papua var. siboga, MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, p. 66, taf. 6, fign. 54-57; taf. 7, fign. 58, 59, 61, 64; taf. 8, fign. 75-77; taf. 9, fign. 84, 85; taf. 12, fig. 1 10.

Bell massive, rounded, and when mature 120 mm. in diameter. There are about 9 rectangular velar lappets with rounded angles in each octant between sense-organs. The 4 interradial ostia of the subgenital porticus are 3 times as wide as the columns between them There are 7 to 10 anastomosing radial-canals between each successive pair of rhopalar canals. Mouth-arms as long as the bell-radius. There are numerous small, rounded clubs upon each of the mouth-arms and also a terminal appendage, which is triangular in cross-section and nearly as long as the bell-diameter.

The ground color is yellowish ( ? ) with orange ( ? ) spots. There are no ring-shaped spots upon the exumbrella. There are 8 violet radial bands upon the rhopalar canals. The terminal appendages of the mouth-arms are sprinkled over with violet spots. The canal- system is rose-colored and the gonads are orange.

This variety is found in the Malay Archipelago, and is described in detail by Maas, 1903. It is distinguished from the typical M. papua by the absence of "eye spots" upon the exum- brella, by its yellow or orange color, and by its nearly rectangular velar lappets.

Mastigias ocellata Haeckel.

Medusa ocellata, MODEER, 1791, Nova. Acta. Phys. Med., N. C., tome 8, Append., p. 27.

Cephea ocellata, PERON ET LESUEUR, 1809, Annal. du Mus. Hist. Nat. Paris, tome 14, p. 361.

Cephea ocei/ata + Hidroticus rujus, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 156, 158.

Mastigias ocellala, HAECKEL, 1880, Syst. der Medusen, p. 625. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, pp.

33, 44, taf. 5, fign. 3-6; 1902, Wissen. Ergeb. I'aldivia Exped., Bd. 3, Lfg. I, p. 49. — MAAS, 1902, Scyphomedusen Siboga

Exped., Monog. 1 1, p. 63.

This medusa is distinguished from M. papua by the peculiar "eye spots" on the exum- brella. These may be described as white circles with a brown center and brown rim. There are also other simple brown spots on the exumbrella. The mouth-arms are shorter than in M. papua, being shorter than the bell-radius, and the terminal clubs are not longer than the bell-radius. Velar lappets more numerous than M. papua, there being about 12 rounded velar lappets between 2 narrow, pointed, prominently projecting, ocular lappets in each octant. There are 15 to 20 anastomosing radial-canals in each octant between the rhopalar canals, instead of about 7 to 9 as in M. papua.

General color reddish, with numerous white, brown-rimmed, and centered "eye spots" on the exumbrella. Tips of terminal club blue.

The medusa becomes about 50 to 60 mm. wide and is found in the eastern parts of the Indian Ocean and in the China Sea. Straits of Sunda, Hongkong in October, Cocos, and Philippine Islands. The Albatross found small medusae in March and April, and a mature one in January in the Philippines, in 1908.

HIIIZOSTOM.K -MASTIfilAS. 681

Mastigias pantherina Haeckel.

Mastigias panlherina, HAECKF.L, 1880, Syst. der Mc.lusi-n, p. 614.— VANH.IH i .x, 1888, Bibliotheca Zoolugica, BJ. I, Heft. 3,

p. 44; 1902, Wissi-n. Ergeb. l'aldn-ia ExpeJ., Bd. 3, Lfg. l, p. 49. Mastigias papua, MAAS, 1903, -Scyphomedusen der Siboga Expcd., Monog. 1 1, p. 63.

This is known only from a preserved specimen, briefly described by Haeckel. It appears to be related to, if not identical with, .17. </i,-lltitn, having the same peculiar "eye spots" on the exumbrella. The velar lappets are said to be truncated and rectangular and to be more numer- ous than in M. ocellata, there being 16 in each octant instead of about 12, as in M. utcllntn. Mouth-arms are much longer than in M. onllntn, being nearly as long as bell-diameter. The simple upper part ot the arm is hardly half as long as the j-winged lower part, whereas in M. oct'lltitii and M. f>nfma the upper part is longer than the lowest part of the arm. Terminal club very much longer than in other forms of Mastigias, being 2 or 3 times as long as the bell-diameter.

Bell dark-brown with white spots ringed with black. Bell-margin black.

Found at Samoa, tropical Pacific.

Mastigias gracile. Dtsmostoma sfacile, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft 3, pp. 35, 45, taf. 4, fign. 5-7.

Disk flatly rounded or hat-shaped, 35 mm. wide, thin at margin, but very thick at apex. Exumbrella besprinkled with irregularly placed clusters of small warts. 8 marginal sense- organs, the marginal lappets irregularly arranged, there being 5 or 10 rectangular velar lappets in various octants; thus some marginal sense-organs may be close together, while others are far apart. There is a wide, well-developed zone ot ring-muscles, confined, however, to the peripheral parts of the subumbrella, its inner edge being bevond the periphery of the arm- pillars. The subgenital ostia are twice as wide as pillars of the arm-disk. These ostia appear double, thus giving the false appearance of 8 instead of 4 genital pus. This is due to the tact that each otthe 4interradial gonads is separated into 2 lateral rays by means of a cen- tral gelatinous flap which divides the subgenital ostium into 2 side-openings.

The 8 mouth-arms are hardly as long as the bell-radius and consist of a simple, short, thick, upper part ot the arm and an expanded j-winged, lower part, which is 3 to 4 times as long as the upper. The lower part is thickly beset with frilled mouths, there being shoif, isolated, gelatinous knobs strewn between the mouths and a short, rounded terminal knob at the free end of each arm, about one-sixth as long as the arm itself. There is also a large cluster of about 8 to 20 linear filaments upon the arm-disk at the bases of the 8 mouth-arms. These are about 1.5 times as long as the diameter ot the bell.

Central stomach large and cruciform, 8 radial-canals arise from it and extend outward to the marginal sense-organs; of these the 4 interradial canals are long and the 4 perradial ones short. Between these 8 main canals are numerous, slender canals which arise from the periphery ot the stomach and anastomose with themselves and with the main radial-canals. All ot these canals are set into communication one with another by means ot the circular canal near the bell-margin. On us outer side the ring-canal gives on* a network ot slender vessels which anastomose over the lappets. The subgenital porticus is very small. Color i :)

Vanhoffen describes 3 examples of this medusa from Assab, on the Red Sea. Tin \ VM u found in September. He gives it the generic name Desmostoma, defining the genus ;is hem;; similar to Mastigias, but with a large cluster ot filaments upon the arm-disk between the mouth-arms. The distinction appears to me to be too slight tor generic, although important for specific, differentiation.

Mastigias (?) rosea Vanhoffen.

Rhizostoma rosra, RETNAUD, 1830, in Lesson's "Centuric zoologiquc," p. 97, planche 34.

Toxoclylus roseus, ACASSIZ, L., 1862, Com. Nat. Hist. U. S., vol. 4, p. 153. — HAECKEI., 1880, Svst. JIT Mrdtiscn, p. 586.—

L> NDENFF.i.n, VON, 1884, Proc. Linnean Soc. \c\v South Wales, vol. 9, p. 288. Mastigias rose;;*, VANHKKMN. 1888, Bibliotheca Zoologica, BJ. I, Hrft. 3, p. 4y

Disk flat and hat-shaped, short, deep radial furrows on the exumbrella surface between the lappets; 56 to 64 ( ?) small, elongate, marginal lappets, all of the same size and shape. 8 separate mouth-arms, hardly as Ions; as the bell-radius; upper part of each arm cylindrical.

682 MEDUS.E OF THE WORLD.

lower half pyramidal and 3-winged, one wing centripetal, the other two centrifugal; outer surfaces of all 3 wings covered with deep furrows which are complexly folded and contain the frilled mouths. A club-shaped, gelatinous appendage arises from the free lower end of each arm and numerous other appendages spring from the sides of the arms between the furrows. No scapulets. 4 horseshoe-shaped gonads.

The bell-margin and frills of the mouth-arms are deep rose color, while the gonads are paler. This species is found in the tropical Atlantic.

Size (?) Exact locality (?) A more accurate and modern figure of this form is greatly to be desired for we can not now be certain even of the generic position of this medusa.

Genus PSEUDORHIZA von Lendenfeld, 1882.

PituJorhiza, VON LENDENFELD, 1882, Zool. Anzeiger, Bd. 5, p. 380; 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 293; 1887, Descriptive Catalogue Australian Museum, Sydney, part I, p. 23. — MAAS, 1903, Scyphomedusen der Siboga Expedi- tion, Monog. II, pp. 53, 71, 80.

Monorhiza, HAACKE, 1887, Jena Zeit. fiir Naturw., Bd. 20, p. 614.

The type species is Pseudorhiza aurosa von Lendenfeld, of Victoria and South Australia.

GENERIC CHARACTERS.

Rhizostomata tnptera with eight 3-leaved mouth-arms, one or all of which terminates in a single large club. No other clubs or filaments among the mouths. 8 rhopalia. ^radial- canals, 8 rhopalar and 8 adradial. The rhopalar canals extend to the bell-margin, but the adradial ones only to the ring-canal which connects with all of the 16 radial-canals. On the outer side the ring-canal gives off an anastomosing network, and on its inner side a number of blindly-ending, centripetal vessels which may anastomose. The wide, circular muscle of the subumbrella is only partially interrupted in the radii of the radial-canals. The sense- club bears an ocellus and there is a shallow, exumbrella sensory pit without radiating furrows. The central mouth persists at the center of the arm-disk.

Haacke's genus Monorhiza is similar to Pseudorhiza, but in Monorhiza only one mouth- arm bears a terminal club, whereas all 8 bear each a terminal club in Pseudorhiza. The distinction may be deemed to be of specific rather than of generic value.

Pseudorhiza is so closely allied to Mastigias that we might readily merge the two genera into one, designating it by the older name Mastigias. In Mastigias, however, one finds small clubs or filaments arising from the sides of the mouth-arms between the mouths, and these are wholly absent in Pseudorhiza; also in Mastigias the inter-rhopalar canals which arise from the inner side of the ring-canal connect with the stomach, whereas in Pseudorhiza they end blindly. These blindly-ending, centripetal canals on the inner side of the ring-canal in Pseu- dorhiza may or may not anastomose. They appear not to anastomose in Haacke's P. haeckelii, but in von Lendenfeld's P. aurosa they are said to form a network; yet von Lendenfeld believes these medusae to be identical, and they are certainly closely related.

The terminal club in all Rhizostomata is merely the naked extension of the axial shaft of the mouth-arm. It is triangular in cross-section as is the arm itself, and the axial duct of the arm extends onward into it. Thus it is not homologous with the club-like appendages and filaments which arise between the mouth-arms.

Pseudorhiza aurosa von Lendenfeld.

Pstudorhiza aurosa, VON LENDENFELD, l88z, Zool. Anzeiger, Bd. 5, p. 380; 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 293, plate 3, I fig.; Ibid., p. 426. — 1887, Descriptive Catalogue Australian Museum, Sydney, Part I, p. 23; 1888, Zeit. fiir wissen Zool., Bd. 47, p. 218, taf. 1 8, fig. I ; taf. 19, fign. 3-7; taf. 20, fign. 14-16; taf. 23, fign. 39, 42, 43, 49-52, 57; taf. 24, fign. 60, 62; taf. 26, fign. 84, 87-92, 94, 95; taf. 27, fign. 98-107, 114 (detailed description).

Umbrella 400 mm. wide, flatly rounded, about 130 mm. high. Exumbrella rough and reticulate. 8 marginal sense-organs and in each octant there are 2 long, narrow, pointed, ocular lappets and 6 velar lappets. Each of the velar lobes consists of 3 secondary lappets. The arm-disk is about as wide as the radius of the umbrella and gives rise to 8 mouth-arms which are about as long as the diameter of the umbrella. There is a central mouth on the (lower) subumbrella side of the arm-disk and 4 pairs (8) of deep gutters extend out from this

HHIZOSTOXI.E — PSEUDORHIZA.

mouth along the lower side of the 8 mouth-arms. These arms are 3-leaved and the free edges ot these leaf-like expansions branch profusely and complexly. The 8 club-shaped axial appen- dages which arise from the lower ends of the 8 arms are each about as long as the diameter of the disk.

The 4 subgenital ostia are somewhat wider than the supports between them. There is a single subgenital cavity. The cruciform, central stomach gives rise to 16 radiating canals, 8 to the sense-organs and 8 to the intermediate positions. These 16 canals are put into connection one with another by a ring-canal. On the outer side of this ring-canal is an anastomozing network of vessels, and extending inward from the ring-canal are 160 blindly- ending, centripetal vessels, 10 between each pair of adjacent radial-canals.

Umbrella colorless, the valleys of the reticulate elevations of the exumbrella violet. The entoderm of gastrovascular cavity brown. Upper parts of mouth-arm grooves rose-colored. Arms colorless and transparent. Mouth-trills along the margins of the grooves and distal ends of the long axial mouth-arm clubs rich violet.

Found at Port Philip, Victoria, and at Adelaide, South Australia.

Described in detail by von Lendenfeld, in Zeit. wissen. Zool. It differs from Haacke's "Monorhiza" in that there are 8 moderately long, mouth-arm filaments, instead of only one very long filament, and the centripetal canals anastomose into a network on the inner side of the ring-canal instead of remaining separate, as in Haacke's medusa.

Pseudorhiza haeckelii Haacke.

PseuJorhiza harcke/ii, HAACKE, 1884, Biol. Ccntralbl., Bd. 4, p. 191.

Monorhiza hatcktlii. H\AI Kt, 1887, Jena. Xcit. fur Naturwisscn, Bd. 20, p. 614, taf. 37, fign. 1-9.

Disk hemispherical to hat-shaped, 200 to 250 mm. wide and 50 to 100 mm. high. Exumbrella roughened with polygonal, wart-like reticulations. 4 elongate, wart-like pro- tuberances upon the subumbrella in the 4 interradii beyond the 4 subgenital ostia. 8 marginal sense-organs Hanked by 16 short, narrow, sharp-pointed lappets. The 48 velar lappets are wide, short, and rounded. There are thus 8 marginal sense-organs and 64 lappets. The central mouth opening is 4-cornered, and the central disk gives rise to 4 pairs ot laterally compressed 3-leaved mouth-arms. Each leaf of these mouth-arms gives rise to many flat, fern-like expansions. A single filament, 300 mm. long, arises from the lower end of one of the mouth-arms; it is spindle-shaped and 3-cornered in cross-section. The 4 subgeni- tal ostia are wider than the gelatinous columns between them. The central stomach is Maltese-cross-shaped and gives rise to 16 canals, 8 extending outward in the radii ot the marginal sense-organs, and 8 being adradial. These 8 ocular canals extend outward to the rhopalia, but the adradial canals end in the ring-canal near the middle zone ot the subumbrella. This ring-canal gives rise in each octant to about 18 narrow, unbranched, non-anastomosing, centripetal canals which end blindly. On the outer side of the ring-canal is a network of anastomosing vessels which fuse with the 8 rhopalar radial-canals. The circular muscles of the subumbrella are well-developed over the peripheral half of the under side ot the bell and are only partially interrupted in the 8 principal radii.

The gonads form 4 U-shaped walls of the subgenital portions and are much folded. I he gastric filaments are so inconspicuous that Haacke tailed to find them, although according to von Lendenfeld they are present. Like C/irystiortj, PsruJorhiza Inii-i-kflii is hermaphroditic, for in addition to the central gonads there are sporadic spermaries situated in root-like ento- dermal filaments in the "gutters" or food crevices of the mouth-arms.

The furrowed network of the exumbrella is violet-brown and the entoderm of the gutters of the mouth-arms dark-red. The large filament glistens in metallic copper-color, and in young specimens it is blue-violet at the base, with a dark-colored, blue and red, spiral, ento- dermal band of color extending throughout its central cavity. The peripheral canal-system of the subumbrella is brownish-red.

Found in the Gulf of St. Vincent, South Australia, and described in detail by Haacke, 1887. Von Lendenfeld regards this medusa as being identical with, or only a variety of, his Pseudorhiza aurosa.

6S4 MEDUS.B OF THE WORLD.

Genus PHYLLORHIZA L. Agassiz, 1862.

Phyllorhiza, AGASSI/, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 158. — HAECKEL, 1880, Syst. dcr Medusen, p. 588. — VON LEN- DENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 296. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 41.

P/iyllorhiza chincnsis L. Agassiz and P. trifolium Haeckel are too imperfectly described to he recognizable, and P. punctata von Lendenfeld, from Australia, is the type species and the only adequately determined form.

Phyllorhiza chinensis is probably Cephea cephea, and P. trifolium is, according to Haeckel, described from a preserved and mutilated specimen. It has 96 marginal lappets. Exumbrella finely granular. Arms with 3 semicircular, pmnately-branched, separated lappets or wings, with 24 long and numerous, short filaments, the largest being equal to the bell-diameter. Bell 75 mm. wide. Japanese Sea.

GENERIC CHARACTERS.

Similar to the closely allied Lychnorhtza but the centripetal vessels which arise from the inner side of the ring-canal join with the central stomach, as in Mastigias, instead ot ending blindly as in Lychnorhiza. Also the ring-muscle of the subumbrella is interrupted in the 8 principal radii. The canal-system resembles that of Mastigias, but the mouth-arms have no terminal clubs.

Phyllorhiza punctata von Lendenfeld.

Ph\llorliiza punclata, VON LENDENFELD, 1884, Zool. Anzeiger, Bd. 7, p. 429 (development). — 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 296, plate 4, I fig.; p. 307, plate 5, figs. 1-4; 1888, Zeit. fur wissen. Zool., Bd. 47, p. 223, taf. 18, fig. 2; taf. 19, fign. 8, 9, n, 12; taf. 21, fign. 17-20, 22; taf. 22, fign. 27-35, taf. 23, fign. 40, 53-55; taf. 26, fign. 79, 80, 86; taf. 27, fign. no, 117 (detailed description). — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. 1 1, p. 60.

Umbrella somewhat flatter than a hemisphere, 500 mm. wide. Exumbrella 50 mm. thick, with a finely granular surface. 8 marginal sense-organs. In each octant there are 2 sickle-shaped ocular lappets, 4 simple lappets near the ocular lappets, and 4 double lappets near the middle of each octant. There are thus 14 lappets in each octant, considering each double-lappet as two. The large, double lappets are partially fused by a basal web, and the ocular lappets are only half as wide as the others and are sharp-pointed, while the others are rounded. Radial furrows extend centnpetally over the exumbrella between the lappets. The arm-disk is thick and a liitle wider than the bell-radius, octagonal in shape and has a canal- system of its own. It is thickly beset with filaments on its ventral side, to which young embryos in the gastrula stage adhere. The 4 subgenital ostia are oval and more than twice as wide as the pillars between them. The eight 3-leaved mouth-arms are two-thirds as long as diameter of umbrella. Their 3 mouth-bearing edges branch pinnately, but the pinnae are only rudi- mentary. The lower parts of the mouth-arms bear numerous, tapering, bluntly-ending fila- ments, some of which are two-thirds as long as the mouth-arms themselves. The circular muscles of the subumbrella are interrupted in the 8 principal radii.

8 radial-canals, 4 perradial and 4 interradial, arise from the cruciform, central stomach and extend to the 8 marginal sense-clubs. A wide ring-canal, at some distance inward from the margin, connects all 8 radial-canals. On its outer side the ring-canal gives rise to a fine- meshed network of vessels (which fuse also with the radial-canals) extending into the lappet zone. On its inner side the ring-canal also gives off a similar network of vessels which connects with the central stomach and with the 4 interradial, but not with the 4 perradial, canals.

The arm-disk, main stems, branches of the mouth-arms, and gelatinous substance of the umbrella are colorless. In the gelatinous substance of the umbrella, close to the surface, are groups of unicellular, yellow, plant cells which give the whole surface a brown color. Also in the gelatinous substance, close to the surface of the exumbrella, there are cloud-like masses of minute, highly refractive bodies which give the medusa a spotted appearance, the spots being whitish. The frilled mouths are brown and the filaments colorless.

This medusa is found in Port Jackson, New South Wales, Australia, and is described in elaborate detail by von Lendenfeld (Zeit. fur wissen. Zool.). He finds that during develop- ment the marginal sense-organs decrease from 24 to 16, and finally to 8.

When the medusa is 15 mm. wide there are 24 marginal sense-organs and 48 marginal lappets. The 2 ocular lappets of each octant are sharp-pointed, narrow, and elongate, while

KHIZOSTOM/E — PHYLLORH1ZA, VKRSUKA. U.S.')

the 4 intermediate marginal lappets are broad and bluntly rounded. The 2 intermediate sense-organs of each octant lie in the clefts of the 2 lappets on both sides of the central fissure of each octant.

When the medusae are about 30 mm. wide the 16 intermediate sense-organs disappear and a new set of 8 sense-organs develops in the middle cleft of each octant. The medusa now has 64 lappets and 16 marginal sense-organs. The 2 lappets on both sides of the 8 velar sense-organs are now double and finally divide completely. When 50 mm. wide the medusa; lose their 8 intermediate sense-organs, and there are then 8 radial and mterradial rhopaha and 80 marginal lappets, von Lendenfeld's observations of this remarkable process of development await confirmation.

Genus VERSURA Haeckel, 1880.

Crossoitoma, used for Mollusca by MORRIS and LYCETT, 1850.

Crossostama, AGASSIZ, L., 1861, Cont. Nat. Hist. U. S., vol. 4, p. 155.— MAAS, 1903, Scyphomeduwn der &A«ga Eiped.,Monog.

ii, pp. 54, 81. Vcrsura-*- Crossostorna, HAECKEL, 1880, Syst. der Mrdusrn, pp. 606, 607.

The older species are inadequately described and we may designate /'. palmata Haeckel, hum the Malay Archipelago, as the type of the genus.

GENERIC CHARACTERS.

Rhizostomata tnptera with clubs and filaments upon the mouth-arms. The 4 perradial canals arise directly from the stomach, but the 4 interradial canals result from the fusion of a number of anastomosing vessels which arise from the interradial sides of the stomach. There is no definite ring-canal, but merely a marginal network of vessels. There are no radial- muscles in the subumbrella, hut the ring-muscles are well-developed.

Among characters of minor importance, the subgemtal ostia are wide openings, wider than the columns between them, and the sense-organs have a simple, exumbrella pit without radiating furrows. At the center of the arm-disk is a prominent, raised cluster of frilled mouths having filaments between them.

The older species are so imperfectly described that it will be hopeless to attempt to determine them and they had best be omitted from further consideration. For example: ""Crossostomn corolliflora" Haeckel is probably a Cotylorhiza; "C. Juhn-uillit" may be a Cato- stylus, and "C. fronJifera" may be a Cassiopea (see Haeckel, Syst. der Medusen, pp. 608, 609).

Versura palmata Haeckel.

Versura fa/mala, HAECKEL, 1880, Syst. dor Medium, p. 606, taf. 40, fign. 9-12. — GOETTC, 1886, Sitzungsber. Akad. \\ i en, Berlin, Jahrg. 1886, p. 836.— VANHOFFF.N, 1888, Bibliothcca, Bd. 1, Heft. 3, p. 42.— HAMANN, 1881, Jena. Zcit. fur Natur- wi^srn., Bd. 15, p. 253.

Bell flat, shield-shaped, 60 mm. in diameter, 20 mm. high. 8 rhopalia set within very shallow niches in the bell-margin. Ocular lappets very small and sharply pointed; the velar lappets \ary greatly in number, ranging from about 4 double ones to 12 in each octant. They are barely discernible, being separated by very short, narrow clefts. Arm-disk about two- thirds as wide as bell-radius; the 4 subgemtal ostia are twice as wide as the perradial columns between them. There is a unitary, narrow, cruciform subgemtal cavity. The 8 mouth-arms are somewhat shorter than the bell-radius. The simple upper axial shaft of each arm is nm quite half as long as the j-winged lower part, which is Y-shaped in cross-section and nearly as wide as long. The free edges of the Y are complexly branched and folded and bear the frilled mouths. Each lamella of the mouth-arm displays 6 to 7 very deep clefts. There are numerous, small, club-shaped vesicles scattered among the mouths and a larger terminal club at the lower end of each arm.

The central stomach is Maltese-cross-shaped. Canal-system of bell ( ? ) There is a marginal zone of circular muscles which are only partially interrupted in the 8 principal radii. Centripetal to this /.one is another muscular zone which is interrupted in the 8 principal radii, the fibers of which are bowed outward toward the areas of interruption. Color (?)

1 [aeckel records this medusa from the Malay Archipelago, and Goette studied specimens from Zanzibar, Singapore, and Nagasaki, japan. It is distinguished only by its indistinct velar lappets and the terminal club of its mouth-arms.

686 MEDUS.E OF THE WORLD.

Versura vesicata.

I'ersura resit'tilti, HAHIKFI., iSSo, Syst. dcr Mrdusen, p. 645.

This is very briefly mentioned by Haeckel. It is closely related to, if not identical with, /'. [Hiltiuitn. hut has twice as many velar lappets. The ocular clefts in the margin are deep and the subgenital ostia are only half as wide as the pillars between them. The vesicular club at the end of each arm is larger than in /'. palmata, being one-fourth as long as the bell- radius. Northwestern coast (?) of Australia. Size, etc. (?)

Versura pinnata Haeckel.

Versiua pinnata, HAECKEL, 1880, Syst. der Medusen, p. 607.

This Cocos Island medusa is very briefly described by Haeckel. Bell flat, 80 mm. wide. 8 deeply-cleft rhopalar niches. 144 lappets. In each octant 16 indistinct quadratic velar, between 12 small, pointed, ocular lappets. Subgenital ostia as wide as the columns between them. Mouth-arms somewhat longer than bell-radius and twice as long as wide. It may be identical with / . palmata, being described only Irom a preserved and presumably contracted specimen.

Versura anadyomene.

Crossostoma anadyomene, MAAS, 1903, Scyphomcduscn dcr Siboga Expedition, Monog. if, p. 56, taf. 7, fign. 65-68. Crossostoma, sp., GOETTE, 1886, Sitzungsber. Akad. Wissen., Berlin, Jahrg. 1886, p. 837.

Bell about 200 mm. in diameter and quite flat. Exumbrella covered with a network of anastomosing furrows, leaving polygonal elevations between them. This network is wide at the center and finer-meshed at the margin, and the general trend of the furrows is mainly outward from the center. Gelatinous substance of bell very thin, being only a few millimeters thick even at center. The canal-system can be seen by looking through the bell from the exumbrella side. There are 8 marginal sense-organs, 4 perradial and 4 interradial. These are small and probably lack ocelli, and on the exumbrella side above each sense-organ there is a small, simple sensory pit without radiating furrows. The 16 ocular lappets which flank the 8 marginal sense-organs are small and lanceolate. In each octant between sense-organs are 8 large, semicircular velar lappets, which alternate somewhat irregularly with about 8 small, narrow, tongue-shaped lappets. The arm-disk is rectangular to cruciform, with long interradial slit-like, subgemial ostia and 4 narrow, perradial pillars between them. The subgenital sinus is a flat, narrow, cruciform space and the genital cross is very narrow. The medusa is very delicately formed, the lower par;s of the mouth-arms being thin and leaf-like.

Each of the 8 mouth-arms is about as long as the bell-radius and very strongly compressed laterally. The upper part of the arm has the form of a knife blade, the sharp edge being inwards (axial) and the thick, rounded side being abaxial. Two rhomboidal, expanded, leaf-like wings arise from the abaxial side of each arm. The lower sides of the two lateral wings and the inner (axial) part of each arm gives rise to numerous, flat, membranous side branches which expand outwardly. These side branches bear the frilled mouths. Small club-shaped vesicles arise from between the mouths of the two lateral, abaxial wings of each mouth-arm, while the ventral side of each mouth-arm gives rise solely to tapering filaments between the mouths. The rows of frilled mouths on the inner (axial) sides of the mouth-arms extend to the center of the arm-disk, where they form a projecting rosette.

A mam canal arises from each of the 4 perradial corners of the stomach and sends branches into the mouth-arms. It is remarkable that each of the lateral, abaxial wings of the lower arms contain 2 separate axial-canals, each of which sends off side branches to the mouths. These side branches do not anastomose and thus there is a double canal-system in each of the lateral wings of the lower arms.

The central stomach is cruciform, the arms of the cross being perradial. 4 perradial canals extend uninterruptedly from the 4 angles of the central stomach to the 4 perradial sense-organs. The 4 canals to the interradial sense-organs do not arise directly from the stomach, but from 4 areas of anastomosing vessels which form a network on the interradial sides of the central stomach. These network-like areas of vessels arise in numerous canals from the entire interradial sides of the stomach. They send out a few branches which join

HHI/OSTUM.E — VKHSritA.

687

the 4 perradial canals. There is no true ring-canal, although all 8 of the radial-canals are placed in communication one with another by a marginal zone of anastomosing vessels which extend into the lappets. There are no radial-muscles in the subumbrella, but there are 2 separate concentric ring-muscles, which are further divided into 8 sectors, the lines of separa- tion being in the radii of the 8 radial-canals. The outer zone of ring-muscles lies close to the bases of the marginal lappets. The inner zone is not a true circle but is widest in the 4i'nterradii and narrowest in the 4 perradial lines. The gonads and canal-system appear to be reddish.

This medusa is described by Maas from a single specimen found in the Malay Archi- pelago by the Sibot;<i expedition. It may be identical with the / i-rsura briefly described by Goette, 1886 (Sitzungsber. Akad. Wissen. Berlin, Jahrg. 1886, p. 837), from the east coast of Africa. Maas gives a detailed description of the medusa. The species is distinguished by its prominent velar lappets, its very thin, delicately formed bell and mouth-arms, and the furrowed surface of its exumbrella.

Versura maasi, sp. nov.

Named in honor of Prof. Dr. Otto Maas in recognition of his notable researches upon medusje.

Bell 90 mm. wide, flatter than a hemisphere and evenly rounded. Exumbrella finely granular, without furrows. Gelatinous substance fairly thick but not very rigid. 8 rhopalia, each with a pigment mass and an exumbrella pit with smooth floor. 112 marginal lappets.

FIG. 416. — Versura maasii. Drawn by the author, from a specimen obtained by the U. S. Fisheries Biirr.ni steamer Albatross in the Philippine Islands.

A, oral view showing (> of the mouth-arms cut off close to the arm-disk. In the lower sector the circular muscles are removed exposing the canal-system. B, magnified view of one of the clubs from between mouths of the mouth-arms. C, mouth-arm seen from the outer (abaxial) side. D, exumbrella view of one of the marginal sense-organs.

The 16 rhopalar lappets are only slightly narrower than the velar lappets. There are usually 12 velar lappets in each octant. The outer edges of all lappets are bluntly rounded. The arm-disk is five-ninths as wide as the bell-diameter in the perradius where it arises from the suhumbrella, but is only one-fourth as wide as the bell-diameter at the level of the origin of the 8 mouth-arms. The 4 interradial subgenital ostia are twice as wide as the perradial arm-disk columns. There is a wide unitary subgenital porticus. The 8 mouth-arms are each one- third as wide as the bell-diameter. The j-winged lower part of each arm is somewhat more than twice as long as the unbranched proximal shaft of the arm. The 2 lateral, outer \MH;:S of each arm are deeply cleft (fig. 416, cl. There are a very few, small, club-like appendages (fig. u) among the mouths of the mouth-arms, but the center of the mouth-arm disk bears a great number of clubs. These clubs are laterally flattened, the largest being only 10 mm. long and besprinkled with nematocyst-bearing warts which are especially numerous upon

688

MEDUSAE OF THE WORLD.

their outer ends. The mouth-arms are strongly compressed laterally, being only 3 mm. in cir- cumferential and ii mm. in radial width at their points ot origin from the mouth-arm disk. A single duct extends into each mouth-arm, but this soon sends off a pair of side branches to the lateral wings, and a pair of secondary branches arises from these and extends down the main shaft of the mouth-arm (fig. 416, c).

There are 8 wide rhopalar canals of which the 4 perradial ones arise directly from the stomach, but the 4 mterradial arise from the confluence of a pair of forks. 7 to 9 narrow vessels arise from each inter-rhopalar octant of the stomach and extend outward toward the bell-margin, giving oft numerous, anastomosing side branches which form a network connect- ing all the canals. There is no definite ring-canal.

Near the hell-margin there is a sharp, angular bend in the subumbrella surface so that the outer annulus of rhe subumbrella extends downward vertically and at right angles with the inner zone ot the subumbrella. There is a wide annulus of circular muscles in the sub- umbrella. These muscle-fibers are unbroken hut somewhat thinned in the 8 rhopalar radii, and the muscular-zone is wider in the interradn than in the perradn, but does not extend to the edges of the arm-disk.

In formalin the rhopalar radial-canals and the proximal parts of all other canals adjacent to the stomach are bluish-purple. The mouth frills are brownish to brownish-purple. The bell is milky and the muscles and gonads dull brownish-yellow.

A single perfect specimen was obtained by the U. S. Fisheries Bureau steamer Albatross on April 8, 1908, along the shore at Mantocao Island, west coast of Bohol, Philippine Islands.

FIG. 417. — Lobonema smithii. Drawn by the author, from a preserved specimen. View of subumbrella. Muscular system shown on right and vascular system on left.

Genus LOBONEMA, gen. nov.

The type species and only known form is Lobonema smithii from Manila Bay, Philippine Islands.

GENERIC CHARACTERS.

Rhizostomata triptera in which the marginal lappets are greatly extended, tapering to pointed ends. Mouth-arms with numerous filaments. Mouth-arm membranes perforated by window-like openings. 8 rhopalia, 16 radial-canals, and a ring-canal which gives off anastomosing vessels on both its inner and outer sides. The inner network does not connect

RHIZOSTOM.E — LOBOXKMA. 689

with the stomach. The suhumbrella exhibits a well-developed system of entire ring muscles. There are numerous prominent, tapering, nematocyst-bearing papilla; upon the exumbrella. All 16 of the radial-canals extend to the bell-margin. There is a sensorv pit on the exumbrella side above each rhopalium and the floor of this pit is furrowed.

Lobonema sraithii, gen. et sp. nov.

This species is named in honor of Dr. llui;li M. Smith, Deputy United States Fish Com- missioner, who found it in Manila Bay. Philipine Islands. The Albatross found a perfect specimen of this medusa, and a quadrant of its disk and all of its mouth-arms were preserved. There were also two other imperfect specimens, so that all three taken together afford data for a partial description of the medusa.

Bell flatter than a hemisphere, 2 56 mm. across from each sense-club to the one 180° from it. Gelatinous substance thick, tough, and rigid. Exumbrella regularly besprinkled with erect, gelatinous papilla; which are largest and most abundant at the center of the exumbrella but dis- appear near the margin and are not seen over the lappets. Near the center of the exumbrella these papilla? are about 6 to 10 mm. apart and each is about ^5 to 40 mm. long and 3 to 5 mm. wide at the base; they are conical, usually more or less curved, and taper to pointed ends. Their surfaces are thickly covered with nematocysts, which give a bristling appearance to the disk of the medusa. 8 rhopalia which lack ocelli in specimens preserved in formalin or alcohol. On the exumbrella side above each sense-club there is a shallow, heart-shaped, senson pit with dendritic ridges over its floor. The rhopalia are flanked hv very small, m al, ocular lappets only 3 mm. long and 2.5 mm. wide. There are 32 (4X81 velar lappets which are most extra- ordinary, each being 90 to 100 mm. long and tapering gradually from base to tip. 1 hey are modified so as to resemble superficially tentacles of semaeostomous Scyphomedusje and trail downward from bell-margin, waving flexibly to and fro as do \eritable tentacles; I can find no muscles in these lappets, however, and do not believe that they can contract and elongate. There are deep clefts in the exumbrella surface between the lappets, but these clef's are bridged over by a thin subumbrella membrane spanning between the lappets. The 8 inter-rhopalar grooves are 35 mm., the 8 rhopalar 16 mm. and the 16 intermediate clefts 31 mm. long. 1 he 8 rhopalar clefts are \ shaped and the exumbrella sensory pit is at the middle of the crotch of the \ with the divided groove on either side of it i see text-figure 418, c ). 1 he grooves between the velar lappets are simple, undivided, linear clefts.

16 radial-canals, 8 rhopalar and 8 inter-rhopalar, leave the central stomach and all extend to the bell-margin. There is a fairly distinct ring-canal about 30 mm. inward from the sense- clubs, and this ring-canal gives rise on both its inner and outer sides to an anastomosing net- work of vessels which connect with the 16 radial-canals, but not directly with the stomach. This network of vessels extends downward throughout the length of the tapering lappets trending mainlv longitudinally but with frequent anastomoses.

The muscular svstem forms an armulus about 68 mm. wide in the subumbrella from the margin of the arm-disk to the /.one of the rhopalia. The circular muscles are powerfully developed, and are only thinned but not broken in the rhopalar radii. There are no radial muscles and no muscles in the lappets.

The arm-disk is 100 mm. wide but as it was cut off, I can make no statements in ref- erence to the size or form of the subgenital ostia or of the gonads.

The 8 mouth-arms are sepaiate, 150 mm. long, and each is 3-winged below. The upper shaft of each arm is 60 mm. and the .{-winged lower part 90 mm. long. It is remarkable that each of the 3 lateral membranes is perforated by 3 windows or openings (see diagram \. text-figure 418). The axial duct of the arm extends down the center and gives offside branches in the tissue between the windows to the mouths. These side branches are joined one to another hv longitudinal canals near the frilled mouths (see text-figure 418, n).

There are numerous appendages upon the mouth-arms arising between the mouths. Those near the lower pointed ends of the mouth-arms are large, spindle-shaped, more 01 K-ss triangular in cross-section and taper to pointed ends. Those arising higher up are more slender, and above these there are mere thread-like filaments. The appendages are usuallv 70 to 100 mm. long, and the large ones contain an axial duct. The general color of the medusa in formalin is milky-gray. The mouths and gonads being darker than other parts.

f>90

MEDUSAE OF THE WORLD.

The U. S. Fisheries Bureau steamer Albatross found this medusa in Manila Bay at the ship's anchorage on April 25, 1908, and again at station D, 5222, between Marinduque and Luzon, 9 miles oft San Andreas Island, on the surface on April 24, 1908.

Dr. Hugh M. Smith tells me that this medusa inflicts a very severe sting upon persons who may venture to handle it, and he believes it to have been the species which stung nine bathers

FIG. 418. — Lobonema smithii. Drawn by the author, from a preserved specimen.

A, diagrammatic illustration of one of the mouth-arms, to show the window-like openings in side walls of arms. B, side view of a mouth-arm, showing canal-system (dotted). C, rhopalium and one of the marginal lobes.

in Manila Bay whose cases were reported upon by Edward H. H. Old, Asst. Surgeon, U. S. Navy. One of these cases proved fatal, and they all occurred during the summer months of 1906-07. The skin where the sting occurs becomes red and vesiculated and "weeps" as does an eczema. Soon general pains develop throughout the body, especially in the lumbar region.

UIII/OSTOM.K— LOBONKMA, THVSAM isTi i\IA.

li'll

The mucous membranes give rise to a thin copious secretion. The patient becomes hysterical, coughs almost incessant Iv and throws himself about the bed, nauseated, weeping, and with an anxious congested face. The pulse becomes rapid and some degree of fever usually develops. The general symptoms develop in from 10 to 15 minutes after the infliction of the sting.

The most efficient remedy was found to be a hypodermic injection of one-sixth to one- eighth grain of morphine sulphate and an external application of an alkaline solution such as bicarbonate of soda. A report upon these cases is presented by Dr. Old in the Philippine Journal of Science, vol. 3, p. 329, 1908.

RHIZOSTOMATA LORIFERA Vanhbffen.

Rhizostomata lorifera, VANILLIN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 45.— MAAS, 1903, ScyphomrdiiM-n der Sibopi

Exped., Monog. n, p. 75. Leptobrachida:, CLAIIS, 1883, Organisation und Entwick. Medusen, Leipzig.— VON LINDENFELD, 1888, Zeit. fur wisteD.Zoo)., Bd.

47, p. 211. — MAAS, 1906, Revue Suisse de Zool., tome 14, p. 104.

CHARACTERS OF THE GROUP.

Rhizostomae with very elongate, narrow, lash-like mouth-arms. The lower parts ot tin arms are 3-winged in cross-section, the mouths being developed upon and near the angK-s.

The upper pans of the mouth-arms are very short and partially fused to the arm-disk by a series of arches spanning from i mi- arm to another. The ring-muscles of the subumlirclla are pow- erfully and the radial muscles weakly developed.

The Rhizostomata lorifera are only a subordinate group ot the Rhizostomata triptera from which they have been demed In the elongation of the mouth-arms and the reduction of the lati-i al expansions of the arms. A description of the genera follows:

Thyianosloma L. AGASSIZ, 1862. Mouth-arms without terminal clubs. 3 rows of frilled mouths extend down the angles throughout the entire length of the lower arm.

Lorifcra HAECKEL, 1880. Similar to Thysanmtoma but with a naked knob at the lower end of each arm.

I^plobrachia BRANDT, i%i&= Leptobrachia+ Ltonura HA ECKEL. Mouths confinc.l to the lower and upper ends of the mouth-arms, so that the mouth-. i' devoid of mouths in the mid-regions of their lengths.

Genus THYSANOSTOMA L. Agassiz, 1862.

Thysanostoma, AGASSIZ, L., 1862, Cont. Nat. Hist. I'.S., vol. 4, p. r ^,. HM<KM, 1880, Syst.der Medusen, p. 615. — VAN BOFFIN, iSSS. Bibliotheca Zoologica, Bd. I, Heft. FIG. 419. — Diagrammatic representa- 3, p. 45. — KISIUNOI-YE, 1895, Zool. Magazine, Tokyo, vol. 7, p. 133.-- Si m i 1/1 ,

lion of the form and position 1898, Dcnkschr. Med. Nat. Gescll., Jena, Bd. 8, p. 44*. MAAS, 1903, Scypho-

of the mouth-arms in the Rhi- mcdusen der Siboga Exped., Monog. 1 1 , pp. 75, 8 I ; njo<>, Revue Suisse de Zool.,

zoslomata lorifera, tome 14, p. 105.

The type species is Thysanostomn thysanura from the Indo-Pacific region. It is possible that Lesson's inadequately described Rliizostoma brachyura may be the same medusa.

GENERIC CHARACTERS.

Rhizostomata lorifera having mouth-arms bearing 3 rows of frilled mouths from base to lower end, without a terminal club.

Among characters of minor importance, the 4 intci radial, suhgenital ostia are wider than the perradial columns between them. There are 8 rhopalar canals, and a ring-canal whii li gives off a network of vessels on both its inner and outer sides. This network connects \\itli all the radial-canals and also at numerous points with the central stomach. The well-de\ el- oped circular muscles are only partially interrupted in the X principal radii. 1 here is a small, shallow, exumbrella pit above each sense-organ, without furrows in the floor of the pit.

692

MEDUSAE OF THE WORLD.

The only difference between this genus and the closely allied Lorifera is that the frilled mouths are developed even to the tips oi the lower ends ot the mouth-arm and there is no terminal club, whereas Lorifera has a naked terminal club.

Thysanostoma thysanura Haeckel.

( ?) Rhizoitoma brachyura, LESSON, R. P., 1829, Voyage de la Coquille, Zoophyt., tome 2, p. 153; 1830, Centurie Zoologique, p. 227, plarche 80.

Th \>anostowti lh\<nnitra, HAECKEI,, iSSo, Syst. dcr Medusen, p. 625, taf. 39, fign. 1-9. — SCHULTZE, L. S., 1898, Denkschr. Med. Nat. GcsclL, Jena., Bd. 8, p. 448, taf. 33, fig. 3; taf. 34, fig. 8. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. ll, p. 75, taf. lo, fign. 93, 94; 1906, Revue Suisse de Zool., tome 14, p. 105. — KISHINOUYE, 1910, Journal Col- lege of Sci., University of Tokyo, vol. 27, art. 9, p. 23.

Thvsanostoma denscrisfum, KISHINOUYE, 1891;, Zoological Magazine, Tokyo, vol. 7, No. 83, p. 133, plate 18, figs. 1-13.

The bell is 90 to 120 mm. wide. The exumbrella exhibits polygonal facets or granular elevations which are larger at the center than at the margin. Its outline is dome-like and flatter than a hemisphere, recalling the appearance of a shield. There are 8 marginal sense-

FIG. 420. — Th\sanostotna thysanura. Drawn by the author, from a specimen taken in a seine by the U. S. Fisheries Bureau steamer Albatross at Panabutan Bay, Philip- pine Islands, Feb. 6, 1908.

A, oral view showing all but one of the mouth-arms cut off. One mouth-arm is cut off close to its point of origin, but the other 6 are cut off at their widest, Y-shaped regions. B, side view of basal part of mouth-arm, with section of same. C, sec- tion near distal end of mouth-arm, somewhat enlarged, showing T-shape of cross- section of arm the and 4 arm-canals. D and E, rhopalar lappets from subum- brella and exumbrella sides respectively.

organs which are flanked by 16 small, pointed lappets and between each successive pair of sense-organs are 6 to 12 bluntly rhomboidal lappets which are very variable in size even in different parts of the same octant. The sense-clubs have a pigmented mass of lithocysts and there is a very small, shallow, simple, exumbrella pit.

The 8 mouth-arms are each about 1.5 to 3 times as long as the bell-diameter; upper arm only about one-twelfth as long as the lower arm. Lower arm delicately formed, j-winged and Y-shaped or T-shaped in cross-section throughout its length; in its upper part it tapers

KlirZnsToM.l-: -Til "is A NnSToMA, I.OKIFKKA. (i<>:;

slightly and then continues throughout the greater part of its length of nearly uniform width, ending m a bl unt, distal extremity, covered with frilled mouths. The wings are thin, longi- tudinal lamelhe, one- being inward 'axial) and two flaring outward i lateral i. The 2 laui.il wings give rise each to short, small, secondary wings near their upper, outermost end. In tin- upper third ot the lower arm the trilled mouths are developed upon the outer sides as will as along the edges of the 3 wings. In the middle third they are confined to the edges of the 3 wings; and in the lower (distal) third, they are developed upon the sides and edges as in the upper third of the arm. Thus in the proximal and the distal thirds of the lower arms the mouths recall the condition seen in the mouth-arms of Mastigiai and Crainhirjnc. Then- are neither terminal knobs nor other appendages upon the mouth-arms, but there are numerous short, slender, filiform, tubular appendages upon the arm-disk.

The arm-disk is quadrangular with rounded angles, with its sides about three-eighths as long as the bell-diameter. The subgenual ostia are large and gaping, 4 times as \\ide as the perradial columns of the disk, and are not narrowed by median flaps. There is a single, lame. but low, subgenital porncus.

There are only ring-muscles in the subumbrella. These are strongest near the margin and the muscle-mass is widest in the 4 interradn. The muscles are onlv partially intei- rupted in the 8 principal radii. The canal-system ot the subumbrella is characterized In the considerable width of the 8 rhopalar canals, which are somewhat wider than the otlu-is. The ring-canal is at some distance inward from the bell-margin and the anastomozing network of vessels extends on both sides of the ring-canal, fusing with the 8 radial-canals and with the central stomach. 4 canals arise from the perradial sides of the cruciform stomach and extend downward through the 4 pillars into the arm-disk. Here each canal divides into 4 blanches, 2 horizontal ones leading into the center of the arm-disk and 2 vertical leading down into 2 of the oral arms. Each arm-canal gives off 3 side branches which together with the axial-canal extend down the mouth-arms, the side branches giving off branchlets to the 3 rows of mouths.

This medusa is found in the Malay Archipelago, from Amboina, Philippines, and Moluc- cas to Japan. It is described in detail by Haeckel, L. S. Schultze, and Kishim>uu-. The exumbrella is violet or mauve colored at its center, grading into russet at its margin. Sub- umbrella flesh-colored. Gonads and mouth russet or hazel-brown. Mouth-arms and arm- disk violet.

Kishinouye's T hysanostoma denser is pum, from Japan, is, I believe, onh the \oun» of T. thysanura. Lesson's Rfiisostoma brachyura, from New Guinea, has a whitish bell with rusty-colored margin and yellowish-red mouth-frills, the general color pattern being MM similar to that of the more highly colored (apane.se medusa.

The dimensions in mm. ot a specimen obtained at Mindanao, Philippine Islands, by the U. S. Bureau of Fisheries steamer Albatross are as follows: Uell, 100 wide; perradial diameter of arm-disk, 74; diameter of arm-disk at level of origin of mouth-arms, 4^; mmt.ii ostium, 40 wide; mouth-arms, 22O long, 24 \vide at widest part, 12 wide at their blunt tips; 8 to 12 velar lappets in each octant; filamentary appendages on the arm-disk, 10 to 15 long; exumbrella finely granular.

In another large medusa from Mausalay, Mindoro, Philippine Islands, taken by the Albatross on June 4, 1908, from a depth of 150 feet, the bell is 120 mm. wide and the mouth- arms IQO long. In a half-grown medusa obtained on the surface at the same time and place the bell is 59 mm. wide with finely granular exumbrella. Mouth-arms 6~ long. Arm-disk 41 mm. wide at its origin from the subumbrella and \\ mm. wide at the level of the origins of the mouth-arms.

Genus LORIFERA Haeckel, 1880.

Himaniosioma, A<,ASSIZ, L.t 1862, Cont. Nat. Hist. U. S., vol. 4, p. 152. — HAECKEL, 1880, V. i uscn, p. 627. \ '•,-.-

HiiFFF.N, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, p. 45. — MAAS, 1903, Scyphomcduscn dcr Siboga E\ 1

pp. 77, 81.

Lorifera, HAF.CKFI., 1880, Ibitl., p. 628.

The type species is L. lorifera ot the Indo-Pactfic region. This genus is distinguished from the closely allied T hysanostoma only by the naked, club-shaped extremities of iis mouth-arms.

The name Himantostoma is preoccupied, baxms; been used by Loew, 1853, lor Diptei.i. \\ e must therefore use Haeckel's alternative name Lorifera.

694

MEDUSAE OF THE WORLD.

GENERIC CHARACTERS.

Rhizostomata lorifera in which the 8 mouth-arms bear rows of three continuous frilled mouths, but terminate each in a naked knob.

Among characters of minor importance the subgenital ostia are usually wider than the perradial disk-columns. The circular muscles of the subumbrella are practically entire. The sense-clubs have each an ocellus and a well-developed, exumbrella pit with radiating furrows.

All the species are from the Indo-Pacific region.

Tabular Description of the Species of Lorifera.

H. lorifera:

H. flagellata:

Diameter of bell in mm.

Number of velar lappets in each octant

Length of mouth-arms in terms of bell- radius (r).

Length of terminal knob in terms of length of mouth-arms.

Color. Where found.

15010 160. Exumbrella smooth. 6 double. 3 to 4r

One-sixtieth; a very small, swollen, oval bulb.

Bell amethyst. Margin white with dark- violet spots. Mouths dark-violet.

Red Sea to Pacific Ocean.

200. Exumbrella granular. 8 rounded.

Two-thirds; slender and tapering.

Malay Archipelago to Hawaiian Islands.

Lorifera lorifera Haeckel.

Rhizottoma lorifera, EHRENBERG, 1835, Abhandl. Berlin. Acad., p. 260. Leplobrachia lorifera, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 154. Himantosloma lorifera, HAECKEL, 1880, Syst. der Medusen, p. 628, taf. 38, fign. 1-6. ( ?) Himaniostoma sueurii, AGASSIZ, loc.cit. p. 152. Lorifera arabica, HAECKEL, loc. cit., p. 628.

Bell 150 to 160 mm. wide with very thin walls and smooth exumbrella surface. 8 rhopalia. 64 marginal lappets. In each octant 6 short, wide, bluntly-rounded, double, velar lappets between 2 rudimentary, oval, ocular lappets. The 4-sided arm-disk is somewhat wider than the bell-radius. The 4 subgenital ostia are 3 to 4 times as wide as the perradial columns between them. There is a narrow, cruciform, subgenital cavity. The 8 long, tapering, whip- like mouth-arms are twice as long as the bell-diameter. Near the arm-disk they are only 5 to 6 mm. wide and taper outwardly, being only 2 to 3 mm. at their ends where they terminate in a naked, oval knob 5 to 6 mm. long. A ventral and dorsal row of complexly folded, frilled mouths is found in the upper half of each mouth-arm, and thus the upper half of the arm is triangular in cross-section, with a double row of mouth-trills at each of the 3 angles. The ventral (inner) ridge of mouths disappears about the middle of each arm, the lower halves of the arms being thus ribbon-like with only the 2 lateral rows ot mouth-trills persisting to the base of the terminal knob. Neither clubs nor filaments between the mouths. There is a wide unitary zone of circular muscles in the subumbrella and apparently no radiating muscle-fibers.

Stomach cruciform, the 4 perradial oral rays of the cross being 60 mm. long and twice as wide (30 mm.) in their outer half as they are near the center of the bell. 8 rhopalar radial- canals arise from the stomach and extend to the marginal sense-organs. These 8 canals are put into connection one with another by a ring-canal at some distance inward from the margin. On its outer side the ring-canal gives off a network of vessels which fuse with the rhopalar canals, and on its inner side there is a wider-meshed network of vessels which fuse with the radial-canals and with the central stomach. There are traces of 8 narrow, adradial canals in the network.

The bell is amethyst-color with a white margin and with a dark-violet spot upon each lappet. The frills of the mouths are dark-violet and the gonads reddish-yellow.

Found at Tur, near Saini, Red Sea, in November.

This medusa may be identical with Agassiz's "Himantostoma sueurn" from the China Sea ; but in this form there are only 5 velar lappets in each octant instead ot 6 as in L. lorifera.

RHIZOSTOM.E — LOUIFKRA. 695

Lorifera lorifera "var." pacifica.

Himaniosloma loriferum, var. facifca SCHULTZE, L. S., 1897, Ablandlung. Scnckcnbcrg. Naturf. Gescll., B.I. 14, Heft l, p. 153, taf. 15, fign. I, la, 6; 1898, Denkschrift. Med. Nat. Gesell. Jena, Bd. 8, p. 446, taf. 34, fig. 9 (young medusa).

This variety is described by Schultze from Ternate and from Amboina, Malay Archi- pelago.

Bell flatly rounded, 200 mm. wide and 50 to 60 mm. high. 8 marginal sense-organs. 64 marginal lappets; each octant has 2 sharp-pointed rhopalar lappets and 6 velar lappets separated one from another by long, deep furrows; the outer edges of these velar lappets are rounded and each lappet usually displays a median cleft, as in L. lorifera, or is even further divided; outer edges of velar lappets evenly rounded. The 4 subgenital ostia are j to 4 times as wide as the arm-columns between them. The 8 mouth-arms are 1.5 times as long as diameter of disk. Thus in a medusa 200 mm. in diameter the arms are each 290 mm. long. The simple upper arm is only 10 mm. long; below this each arm expands into a ^-winged appendage, with two outer and one inner wing. This 3-winged part of mouth-arm is very short and extends below in a very long, slender, 3-sided lash, the angles of which bear frilled mouths. This lash terminates below in a small, vesicular, naked knob. The gastric canal which enters each lower mouth-arm sends out a longitudinal branch into each of the 2 dorsal wings. These branches are put into communication with the central canal of the arm In- frequent cross-branches, and the side branches into the mouth-grooves often anastomose.

In the middle of the bell is a dark blue-violet area. Near the bell-margin the color is brownish or white. The marginal lappets are violet. The smooth, outer side of the upper arm is transparent. The thick, proximal parts of the lower arms are light-brown in their basal parts, but throughout the greater portion of their lengths they are violet.

This "variety" is probably identical with Haeckel's L. lorifera from the Red Sea. The slight differences mentioned by Schultze may readily be due to individual variation. For example, in the medusa from the Malay Archipelago the lower side of the arm-disk along the lines of the 8 axial rows of mouth-openings is beset with a felt-like mass of long, thin filaments. These are absent, however, in Haeckel's medusa from the Red Sea. Schuhze has seen Haeckel's original specimen in Berlin and finds that it is a male, whereas the medusa from the Malay Archipelago is a female. It is possible, therefore, that this difference in the condition of the lower surface of the arm-disk may be sexual.

Lorifera flagellata.

Himantoitoma fagtllata, HAECKEL, 1880, Syst. der Medusen, p. 629. — MAAS, 1903, Scyphomcduscn der Siboga Expedition,

Monog. 11, p. 77, taf. 10, fign. 87-92; taf. n, fig. 101.

The bell is flatly rounded and may be 200 mm. in width. The gelatinous substance is thick, tough, and of a porcelain-like whiteness. The exumbrella bears fine granulations, and near the margin are light-brown punctations, especially numerous over the marginal lappets, where they are rendered especially conspicuous owing to the white color of the under- lying gelatinous substance.

There are 8 marginal sense-clubs each with a large swollen end containing a concretion and a pigment-spot of horseshoe shape. The covering scale over each sense-club is wider than it is long, and there is a well-developed sensory pit upon the exumbrella side. The bottom of this pit exhibits radiating furrows. The 8 sense-clubs are flanked by 16 short, pointed, ocular lappets, and between each successive pair of sense-organs are typically 8 large, rounded, velar lappets. Thus there are in all 80 marginal lappets.

The arm-disk is 8-sided and the 4 interradiul, subgenital ostia are nearly twice as wide as the pillars between them. These pillars of the arm-disk are peculiar. Near their points of origin from the subumbrella each pillar is dmded so that 2 arches of gelatinous substance extend downward to the base of the upper arm. Spanning these arches is a well-developed, gelatinous membrane which also spans the 4 interradial spaces between the anii-disk-pillars and overlaps the 4 subgenital ostia. This peculiar arrangement is well described by L. S. Schultz, 180,8, in L. lorifern var. pacifica (see Denkschr. Med. Nat. Gesell., Jena, Bd. 8, p. 447). The arches and the cross-spanning membrane extend so far down the length of the upper arm that only a small portion of the latter is free.

696 MEDUSAE OF THE WORLD.

The 8 mouth-arms when contracted are hardly longer than the bell-diameter. The lower arms are free and taper to their pointed lower ends. They are about 6 times as long as the upper arms. At the upper end of each of these lower arms there are 2 abaxial wings so that the arm is here 3-winged in cross-section and the frilled mouths are developed only along the thin edges of the 3 membranous wings. The main shaft of the lower arm is, however, triangular in cross-section and the mouths are developed upon the sides as well as upon the angular edges ot the arm. Each lower arm terminates at its pointed lower end in a long, tapering filament which is about two-thirds as long as the lower arm itself. Numerous, short, slender filaments arise from between the mouths, especially along the lines of the angular edges of the lower arm. There are no club-shaped appendages.

Stomach cruciform, the arms ot the cross wide and not quite as long as the center, where- in the arms come together. Thus the stomach is relatively wider than in other species of Lonjera. The canal-system of the bell consists of 8 canals in the radii of the sense-organs, which are put into communication one with another by a network of anastomosing vessels which arise not only from the 8 radial-canals but. from the edges of the stomach. There is no clearly developed ring-canal and it is difficult to determine the number of canals which arise from the stomach between each successive pair of rhopalar canals. There is a very wide zone of circular muscle-fibers in the subumbrclla. This muscle is only somewhat thinned but not actually interrupted in the 8 principal radii. The 4 gonads are horseshoe-shaped and com- plexly folded. This medusa is found at the Hawaiian Islands and in the Malay Archipelago.

In a small specimen found by the U. S. Fisheries Bureau steamer Albatross at station 05226, in the Philippine Islands on May 4, 1908, the bell is 50 mm. wide and mouth-arms 56 mm. long, the slender, tapering filaments at the ends of the arms being 18 mm. and the mouth-bearing parts of the arms 38 mm. long.

Genus LEPTOBRACHIA Brandt, 1838.

Ltptobrachia, BRANDT, 1838, Bull. Acad. Sci. St. Petersbourg, tome i, p. 191. — AC.ASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4,

p. 154. — MAAS, 1903, Scyphomedusen der Siboga Exped., Monog. u, p. Si. Lr/ttobrachia+Leonura, HAECKEL, 1880, Syst. der Medusen, pp. 630, 651. Leonitra, HAECKEL, 1881, Deep-Sea Medus;e Challenger Expedition, Zool., vol. 4, p. 133. Leptobrachia + Leonura, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 45.

GENERIC CHARACTERS.

Rhizostomata lorifera in which the long, linear mouth-arms bear no frilled mouths near the middle of their lengths; but near their points of origin from the arm-disk there is a ventral row of mouths, and below the naked mid-region there are 3 lines of mouths, I ventral and 2 dorsal. The mouth-arms terminate below in a naked pointed end, free of mouths.

Among characters ot minor importance, the slit-like subgenital ostia are wider than the columns between them. 16 radial-canals extend to the bell-margin and a well-developed ring-canal gives off a network ot vessels on both its inner and outer sides; these networks fuse with the radial-canals. A unitary, circular muscle is in the marginal zone of the sub- umbrella.

Leptobrachia leptopus Brandt.

Rhizostoma leptopus, CHAMISSO ET EYSENHARDT, 1821, Nova Acta Phys. Med. Nature Curios., tome 10, p. 356, taf. 27, fign. i,

A and D.

Leptobrachia leptopus, BRANDT, 1838, Bulletin Acad. Sci. St. Petersbourg, tome I, p. 191. Leonura terminally, HAECKEL, E., 1880, Syst. der Medusen, p. 646; 1881, Deep-sea Medusae Challenger Expedition, Zool., vol. 4,

p. 133, plate 32, figs. 1-8. Leonura leptura, HAECKEL, 1880, loc. cit., p. 631.

The following description is derived from Haeckel's account of his "Leonura termi- nalis" which is only a modern name for Brandt's Leptobrachia leptopus =Rkizostoma leptopits Chamisso and Eysenhardt.

Bell flatter than a hemisphere, 80 mm. wide. Exumbrella covered with regularly arranged, polygonal elevations bordered by furrows. 8 rhopaha. 80 marginal lappets. All of the lappets are sharply pointed and are largest at the middle of each octant, the smallest being adjacent to the rhopalia, the lappets increasing successively in size and being largest midway

KHIZOSTOM/E — LEPTOBRACHIA. 697

between the rhopalia. Converging furrows extend up the sides of the exumbrella from the clefts between the lappets. Arm-disk 4-sided, rarely as wide as the bell-radius, with subgtnital ostia 3 times as wide as the columns between them. A unitary, cruciform, subgenital cavity. The 8 slender mouth-arms are about as long as the bell-diameter. The arms are triangular in cross-section and end below in a triangular, pointed, naked extremity nearly one-fourth as long as the entire arm itself. 8 rows of frilled mouths radiate outward from a raised rosette of frills at the center of the arm-disk and extend down the ventral angle of each mouth-arm for a distance about one-fourth the length of the arm. Below this the arm is naked, triangular, and devoid of all mouths for about one-fourth of its length. Below this naked region are 3 double rows of frilled mouths, i on the ventral and 2 on the dorsal angles of the arm cmi-iing a length equal to about one-fourth the arm; below this region is the naked terminal club. Thus from base to lower end we find: (i) a length wherein there are only ventral mouths; (2) a mid- region devoid of mouths; (3) a part wherein there are 3 double rows of frilled mouths, i \i-ntral. 2 dorsal; (4) the pointed, naked, terminal club. There is a unitary marginal zone of ring- muscles in the subumbrella.

The cruciform, central stomach gives rise to 16 radial-canals, 4 perradial, 4 interradial, and 8 adradial. All extend to the bell-margin and are connected by the ring-canal at some distance inward from the margin. A network of anastomosing vessels connects the ring- canal with the radial-canals on the inner side. On its outer side the ring-canal gives off a forked canal into each velar lappet and a network of anastomosing vessels which connects with all of the canals in the lappets.

Found by the Challenger expedition near Juan Fernandez Island, off the Pacific coast of South America.

Haeckel's " Leonura leptura" from near New Zealand, is probably another name tor L. terminalis. It differs only in having rectangular instead of pointed velar lappets and the mouth-arms are 3 times as long as the bell-diameter, whereas the arms of L. terminalis are said to be only about as long as the diameter of the bell. The "quadratic" marginal lappets of L. "leptura" are probably due to the loss of their originally pointed ends, an accident which frequently occurs to Scyphomedusae.

It seems probable that Rhizostoma leptopus of Chamisso and Eysenhardt, 1821, is the same medusa. It is described from the Radack Islands, tropical Pacific. The mouth-arms

are not quite twice as long as the bell-diameter, thus resembling

Haeckel's L. terminalis.

The bell is light-violet, the margin and frilled mouths

being darker. 32 reddish-violet spots on the exumbrella near

the margin. Gonads yellow.

RHIZOSTOMATA SCAPDLATA Vanhoffen.

Rhhonomaia icapulata, VANHOFFEN, 1888, Bibliothcca Zoologica, Bd. i, Heft. 3, p.

42. — MAAS, i903,Scyphomedusen der Siboga Expedition, Monog. n, p. 72. Stomolophid<x+ Rhizos1omidiT,CLAUS, l883,Untersuch.uber Organisation und Entwick.

Medusen. — VON LENDENFELD, 1888, Zcit. fur wissen. Zoo!., B>l. 47, p. 208.

Rhizostomae in which each of the 8 mouth-arms bears a pair of wing-shaped outgrowths, called scapulets, or shoulder ruffles which arise from the dorsal side of each arm near its Fin. 421.— Diagrammatic representa- point of origin from the arm-disk. Frilled mouths are devel- tion of shape of mouth-arm in Oped upon the upper and outer sides of these scapulets as u. II

Rhizostotnnta icapulata. r i TI • i

as upon the lower parts ot the mouth-arms. 1 he circular

muscles of the subumbrella are powerfully and the radial-muscles weakly developed or absent. A description of the genera follows:

Rhizostoma CUVIER, 1800. 8 free mouth-arms, the lower parts of which are Y-shaped or j-wingrj in cross-section. These 3 wings meet at a point at the lower end of the arm, and a naked, j-corncred, club-like appendage arises from this point. There are neither secondary clubs nor filaments upon the mouth-arms.

Rhofilema HACCKEL, 1880. Similar to Rhizouoma, but with numerous dubs or filaments upon the mouth-arms.

Eafilema HAEI-KF.I., 1880. Similar to Rhizoiloma but there are neither clubs nor filaments upon the mouth-arms.

Slomolophus L. AC.ASSIZ, l86i= Brachiolofhus + Stomolophus HAKICM. 1880. 8 laterally coalesced mouth-arms form- ing an 8-sided throat-tube for the central mouth. Lower ends of mouth-arms arc free and branch complexly.

698

MEDUS.E OF THE WORLD.

Genus RHIZOSTOMA Cuvier, 1799, sens, restr.

Rhizoslome, CUVIER, 1800, Bull, des Sci. Soc. Philomathique de Paris, tome 2, p. 69, planche 4.

Rhizosloma, PERON ET LESUEUR, 1809, Annal du Museum Hist. Nat. Paris, tome 14, p. 362. — ESCHSCHOLTZ, 1829, (in part),

Syst. der Acal., p. 45. — DE BLAINVILLE, 1834, Manuel d'Actinologie, Paris, p. 297. — LESSON, 1843, Hist. Nat. Zooph.

Acalephes, p. 411. — GEGENBAUR, 1856, Zeit. fiir wissen. Zool., Bd. 8, p. 210. — AGASSIZ, L., 1862, Cont. Nat. Hist. U. S.,

vol. 4, p. 150.

Pilema, HAECKEL, 1880, Syst. der Medusen, p. 591. Rhizostoma, CLAUS, 1883, Organisation und Entwick. Medusen, p. 60, Leipzig. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I,

Heft. 3, pp. 31, 43. — MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. n, p. 80.

The type species is Rhizostoma pulmo of the Mediterranean.

GENERIC CHARACTERS.

Rhizostomata scapulata with 16 scapulets upon the outer sides of the 8 mouth-arms. The 8 mouth-arms are free, not fused together. Lower arms 3-winged, each terminating in a single, club-like, gelatinous appendage. There are no other clubs, nor filaments among the mouths. The 4 subgenital ostia are narrow cross-slits, each constricted by a wart-like papilla upon the subumbrella. 16 radial canals, 8 rhopalar and 8 adradial, all of which extend to the bell-margin. A network of anastomosing vessels arises from the outer halves of these 16 radial-canals, and this network gives rise centripetally to 16 blindly-ending areas in the sectors between the radial-canals. There is no marginal ring-canal, but the most direct and widest connection between the radial-canals is through the middle of the zone of anastomos- ing vessels. 16 triangular areas of circular muscle-fibers alternate with the 16 radial-canals. The marginal sense-clubs lack ocelli. There is an exumbrella pit above the sense-club and the bortom of this depression is furrowed with radiating ridges.

This genus is distinguished from Eupilema Haeckel by having 8 terminal clubs upon its mouth-arms whereas these are absent in Eupilema. It is distinguished from Rhopilema by

Synopsis of the varieties of Rhizostoma pulmo.

	R. pulmo.	R. lutea.	R. octopus.	R. corona.	R. capensis.
Diameter of bell	150 to 600	100 to 300	As in R. pulmo.	200 to 400	200 tO 300 ( ?)
in mm.
Character of ex-	Finely granular.	Rough with oval	As in R. pulmo.	Smooth ( ?)	Smooth or finely
umbrella surface.		warts.			granular.
Number of mar-	80	80	96 tO 112	140 to 1 80	?
ginal lappets.
Shape of velar lap-	Semicircular.	Short, oval.	Short, pointed.	Small, truncated.	Semicircular.
pets.
Length of upper	Longer than lower	As in R. pulmo.	Shorter than lower	Nearly twice as long	Not as long as lower
arm.	arm.		arm.	as lower arm.	arm.
Length and shape	Shorter than, or	Longer than entire	Longer than upper	Somewhat shorter	Half as long as upper
of terminal club.	equal to, upper	arm. With long	arm with a slender	than upper arm.	arm. Pyramidal,
	arm. Widest near	slender basal stalk	basal stalk and	Width nearly uni-	3-cornered with
	base. Constricted	and swollen club-	swollen club-	form throughout.	toothed angles and
	at base. No basal	like outer end.	shaped outer end.	Terminal knob	bluntly pointed
	stalk.			with toothed angle.	end.
Color.	Bell milky-yellow,	Warts of exum-	As in R. pulmo.	?	Bell and clubs
	occasionally red-	brella reddish-			bluish. Mouth-
	dish. Marginal	brown. Frilled			frills brownish-red.
	lappets blue or vio-	mouths yellowish.
	let. Mouth-frills	Terminal club
	orange-yellow to	deep purple-brown.
	brownish-red or
	violet.
Where found.	Mediterranean.	Straits of Gibralter.	Atlantic coasts of	Red Sea at Suez and	Cape of Good Hope,
			Europe, France to	Tur.	South Africa.
			Scotland.
Remarks.		Described in detail	Closely related to	Imperfectly known .	So imperfectly
		by Grenacher and	R. pulmo, but	Apparently closely	known that it can
		Noll.	distinguished by its	related to R. pulmo.	not be determined.
			swollen, club-like,
			terminal append-
			ages.

PLATE 73.

Fig. i. Rhizostoma pulmo, 0.75 natural size. Zoological Station, Naples,

Italy, November 29, 1907. Fig. 2. Cotylorhiza tuberculata, 0.75 natural size. Zoological Station, Naples,

Italy. November 30, 1907.

Drawn from life, by the author.

PLATE 73

-•

XII

£

*

,.

*

*

HHIZOSTOMjE — KHIZOSTOMA. 699

having but a single filament (a terminal one) on each mouth-arm, while in Rhopilema there are, in addition to the terminal knob, many lateral appendages between the frilled mouths. The varieties ofRhizostoma are known only from the Mediterranean, Red Sea, and At- lantic coasts of Europe and Africa, and are closely related to R. pulino of the Mediterranean; distinguished one from another only by the relative lengths, and the various shapes of the terminal clubs.

Rhizostoma pulmo Agassiz. Plate 73, fig. i.

Potta marina, ALDROVANDI, 1642, Zoophyt. Lib., tome 4, pp. 73, 76. Also; Pulmo tnarinus, pp. 75, 77.

Medusa pulmo, MACRI, 1778, Atti Real. AcaJ. Sci. Napoli, vul. 2, p. 45, tav. i. — LINNE, (Gmelin), 1788, Systema Natural, Ed. 13, Pars. 6, p. 3155.

Rhizostotna aldrorandi, PERON KT LlSUEUR, 1809, Annal. du Mus. Hist. Nat. Paris, tome 14, p. 362, No. 102. — DELLE CHIAJE, ]S.!2, Mem. Anim. senza \Vrt., Kci;nu Napuli, tav. 74, fig. lo; tav. 75, figs. l-io; Ibid., 1841, vol. 7, tav. 142, 143.

Cephea aljrorandi, DE LAMARCK, iSib, Syst. Anim. sans. Vert., tome 2, p. 517.

Rhizostotna cuvieri, CHAMISSO FT EVSENHARDT, 1821, Nnv.i Acta Acad. Nat. Cur., Leop, C., tome 10, p. 377, plate 34. — DE BI.AINVILLE, 1834, Manuel d'Artinnlo^ic, p. 297, planche 44, fig. I.

Rhhostoma pu/mo, AUASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 150. — CLAUS, 1883, Untcrsuch uber Organisation und Entwick. der Medusen, p. 43, taf. 12-15, nRn< 86, IO5 (development of the rphvr,i). <JK-\KH K. iSS4, Arhi-it. /..ml. Inst. \\ U n. K.I. s. p. 343 (seasonal distribution).— VANHOFFEN, 1888, Bibliotlu-i a /.»>!. mi a, Bd. i, Heft. 3, p. 31. — DE VESCOVI, 1895, Zool. Results, vol. I , p. 37. — VON UEXKULL, 1901, Mitth. Zool. Sta. Xe.iprl, lid. 14, p. 620 (rhythmical pulsation). — BF.THE, I 903, Allgemeine Anat. and Physio] . Nervensyst., pp. 87, 90, 1 08, 410, 426, 432, etc., fit-n. ;;- ;^, 83, 87, etc. (rhyth- mical pulsation); 1908, Archiv fiir Ges. Physiologie, Bd. 124, p. 1541; IhiJ., 1909. Bd. 1 27, p. 219. — HARGITT, 1904, Journal of Exper. Zool., Baltimore, vol. i, p. 73, figs. 1-6 (regeneration).

Rhizostotna cuvieri, BRANDT, A., 1870, Mem. Acad. Sci. St. Petersbourg, tome 16, No. 6, 29 pp., I taf. (detailed description). — C'JAI'S, 1877, Denkschrift. \Vien Acad.. Bd. 38, p. 47, plate 10, ll; 1881, Zool. An/eiger, Bd. 4, p. 79 (young ephyra), 1883, Arbeit. Zool. Inst. Wien, Bd. 5, p. 9, taf. 2, fig. 12 (young ephyra); 18*4, Arbrit. /ool. Inst.Wien, Bd. 5, p. 169; taf. 2, fig. 12 (ephyra). — BLANC HARD, 1883, Zool. Anzeigcr, Bd. 6, p. 67 (the blue coloring matter is not cyanein). — HESSE, 1895, Zcit. fiir \vissen. Zool., Bd. (o, p. 411, taf. 20-22 (nervous system and sense-organs).

Pilttna pulmo, HAF.CKEL, 1880, Svst. dcr Molusen, p. 591 (record of literature). — HAMANN, 1881, Jena. Zeit. fiir Naturwissen, Bd. 15, p. 250, taf. 10, fii;. 13 (structure of mouth-arms).

Bell pyriform, somewhat higher than a hemisphere, usually not more than 150 mm. in diameter, though specimens 600 mm. wide may occasionally be found. Surface of exumbrella finely granular, being covered with small nettlmg-warts. 8 marginal sense-organs, each containing an orange-colored mass ot concretions of entodermal origin; no ocellus. Above each sense-organ on the exumbrella side is a wide triangular pit, the bottom of which exhibits diverging furrows. Each sense-organ is flanked by a pair of narrow, elongate, lanceolate, sharp-pointed rhopalar lappets. 8 evenly rounded, velar lappets, all similar each to each in size and shape in each octant. Thus there are in all 80 marginal lappets (16 rhopalar + 64 velar).

The total length of the mouth-arms, including their terminal clubs, is about equal to the bell-diameter. In its upper part the arm-disk is 4-sided and narrow, but below it widens out, becomes 8 to i6-sided and gives rise to the 16 (8 pairs) short, simitar-shaped scapulets having fringed mouths upon their upper, convex sides. The 8 mouth-arms are each 3-winged, or Y-shaped in cross-section, two of the wings being directed outward, one being centripetal. These wing-like expansions bear numerous mouths, the lips of which are fringed by a row of short, flexible, knobbed tentacles.

The terminal knobs are triangular in cross-section, somewhat contracted in the middle of their lengths and with a simple, central canal. They are usually a little shorter than the upper arms, but may equal or slightly exceed them in length. The mouth-bearing, lower arms are somewhat shorter than the free upper arms between the zone of the 16 scapulets and the winged portion ot the arms. Ordinarily the scapulets are hidden away under the con- cavity ot the subumbrella. The 4 subgenital pits are narrow, slit-like and with their open- ings constricted in the middle by a knob-shaped protuberance upon the floor of the subum- brella. The 4 invaginated, genital sacs are small and separated completely one from another.

The cruciform central stomach gives rise to i') radiating canals, 8 of which extend to the sense-organs and 8 are intermediate in position; all reach the bell-margin. A network of anastomosing vessels places the outer halves of the radial-canals in connection one with another, and extending inward between the id radial-canals are 16 blindly ending areas composed of a network of vessels. There is no distinct ring-canal at the bell-margin, but the connections between the radial-canals an- wider along the inner edge of the zone of anas- tomosing vessels than elsewhere, i'1 deltoid areas of circular muscles alternate with the radial-canals and are more or less completely separated in the radii of the canals themselves.

700

MEDUS.E OF THE WORLD.

The canal-system of the mouth-arms is as follows: 4 vessels arise from the perradial angles of the lower side of the central stomach and extend downward into the arm-disk in the 4 perradii. These 4 primary canals bifurcate and the 8 branches extend down the 8 mouth- arms. The 16 lateral vessels which go into the scapulets arise from these 8 mouth-arm canals. The central mouth is always present in very young medusx but it usually disappears in the adult. When this mouth is present, or more or less vestigial, we often find a correspond- ing complexity in the mouth-arm canals, for in this case the 4 perradial canals from the corners of the lower part of the central stomach extend downward beyond the points of origin of the

FIG. 422. — Rhizostoma pulmo. From life, by the author, at Naples Zoological Station, December, 1907.

I, oral view of bell with mouth-arm removed. One half of the surface shows sector of circular muscles, and the other half shows the muscles removed to reveal the canal-system, n, side view of mouth-arms with sections of same, in, section of arm-disk immediately below scapulets. iv, oral view of arm- disk showing persistent central mouth opening, v, sense-organ from exumbrella side.

8 mouth-arm canals; upon reaching the cruciform, central mouth, each of these 4 canals forks and the 8 branches extend outward along the 8 lines of the frilled mouths, becoming confluent with the 8 main, mouth-arm canals in the j-winged parts of the mouth-arms. A detailed description of the canal-system is given by A. Brandt, 1870.

The gelatinous substance of the disk is creamy-yellow to milky, or rusty-yellowish and translucent. Marginal lappets dark cobalt or violet to blue. The sensory-clubs are tipped with orange, which colors the concretions. The frilled mouths are dull orange, yellow, or brownish-yellow, and the outer parts of the terminal knobs are tinged with the same color. Gonads yellowish, all other parts translucent.

RHIZOSTOXLE — Rlll/.i IST< .MA. 701

This medusa is common in the Mediterranean. It is found throughout the year, but is most abundant from June until August, becoming ripe in August and September. Very small medusae are often found in June. Mature individuals are occasionally seen in midwinter.

Claus has studied the development of the pelagic ephyra. When 3.5 mm. in diameter the ephyra has a central, cruciform mouth, the 4 lips of which are lined by a row of knobbed tentacles as in Aurcllla. There are 8 pairs (16) of velar lappets and 8 pairs (16) rhopalar lap- pets. 16 radial-canals and a simple, circular canal. In this stage the 8 adradial canals end in the ring-canal, but the 8 others go to the bell-margin. The velar lappets develop in pairs, as in the Discomedusa; and in Stomolofhus, not singly as in Aurellia or Cot\lorluza. The 8 mouth-arms arise from paired, terminal tolds of the 4 primary rays of the cruciform, cen- tral mouth. A detailed description of the young ephyra is given In C'laus, 1885.

The rhythmical pulsation ot this medusa has been studied by von Uexkiill, who found that if the marginal sense-organs be mechanically confined the pulsation is hindered. His conclusion, however, that the stimulus which produces pulsation is mechanical in nature and may be likened to that produced by the clapper of a bell in striking against the margin seems to me improbable. Pressure upon the nerve-center might readily interfere with the activity of the sense-club, and any confinement which cuts oft" the supply of soluble calcium from the sea-water would soon cause pulsation to cease.

A very suggestive and important series of studies of the nature of the pulsation stimulus in this medusa and in Cotylorhiza tuberi-uliitii was carried out by Bethe, 1903-1909. He finds, in 1903, that under normal conditions hundreds ot pulsations follow quite regularly one after another, with only an occasional pause ot brief duration. The medusa pulsates almost inces- santly. According to Bethe there are many analogies between the pulsation of this medusa and that of the vertebrate heart. For example, the "all or none" principle applies to medusa;, as does also the phenomena of the extra systole and corresponding compensation- period of rest. The medusae also show a refractory stage during systole in which they are insensible to stimuli, as was demonstrated by Marey, 1876 (Travaux du lab., p. 73), for the vertebrate heart.

There is an increase in the time that elapses between stimulation and response, and also in the duration of the pulsation itself as the temperature is lowered from 25° to 13° C. The pulsation-stimulus is nervous in nature, being transmitted by the diffuse, nervous network of the subumbrella. Indeed, there are areas of the subumbrella which are wholly without muscles; nevertheless the pulsation-stimulus passes freely over these to the muscular areas beyond. Bethe gives a good series of figures showing the histological character ot the nerve plexus which forms a network between the epithelium and the deep-lying, muscular layer of the subumbrella. The sense-organs are physiologically speaking only highly differentiated parts of the nerve-plexus of the subumbrella.

Under normal conditions the pulsation-stimulus originates in the marginal sense-organs, yet in medusa; (such as Cotylorhiza} which have an inner zone of radial and an outer zone of circular muscles in the subumbrella the radial-muscles contract before the circular, although they are farther away from the sense-organs. This is due, as Bethe shows, to the fact that the latent period (i. ,-., the time that elapses between stimulus and response) is longer for the cir- cular than for the radial muscles.

The pulsation is a reflex due to a constantly present stimulus, and the refractory stage produces periodicity (rhythm) in the responses. The nerves can not send forth a new con- traction-stimulus until a definite period of rest hns elapsed.

Bethe, 1908, 09 (Pfliiger\ Aivlm. fiir ges. Physiologic, Bdn. 124 and 127), has continued his studies of the rhythmical pulsation of Rhizostoma pulnw at Naples. He finds that artificial sea-water will not sustain life and pulsation as well as does natural sea-water unless a small amount of CaCo3 be added to the solution. This improvement of the artificial sea-water is not due he believes to the addition of Ca or to the neutralization of an acid, but is caused by the presence of the undissociated molecules of CaCor It will be recalled that Rogers, 1905 ( Journal Experimental /.ool., vol. 2, p. 24t)\ found that the addition of small amounts of CaCo3 to solutions containing the pulsating heart of the crab Br achy not us had a beneficial effect. I Ie attributed this, however, to the neutralization of free acid in the solutions.

702 MEDUS.E OF THE WORLD.

NaCl in the absence of the other salts of sea-water at first stimulates and later retards pulsation, and this effect is commonly reversible. According to Bethe, the absence of calcium in the presence of the other salts of sea-water causes all movement to cease but normal pulsation is restored by restoring the calcium to its normal amount. In a slight excess in tiom 2 to 5 c.c. of i molecular CaCl2 in 100 sea-water calcium operates for a long time fo accelerate and strengthen pulsation. In larger excess such as 10 CaCl2 in 100 sea-water ,t retar.ls pulsation and produces an abnormal duration of systole. Magnesium chloride and sulphate produce a marked primary retardation, without any final acceleration. Potas- sium tends primarily to stimulate the rhythmical movement in Rhlzostoma. Thus, accord- ing to Bethe, Na, K, and Ca of the sea-water are primarily stimulants for pulsation, but are antagonized by Mg which alone is an inhibitor ot pulsation, and thus a balanced solution is formed. Na and Mg exert their effect primarily through the marginal sense-organs, and Mg also acts upon the general system of muscles. Na, on the other hand, affects the nervous sys- tem. Potassium exerts its influence through the marginal sense-organs but has little or no direct influence upon the muscles and nervous network. Calcium in slight excess exerts all or nearly all of its effect through the marginal sense-organs.

Aluminium is an inhibitor of pulsation and is relatively more powerful in this respect than is magnesium. MgSO4 is a less powerful inhibitor than MgCl2 and the order of efficiency as stimulants of the sodium salts is beginning with the most powerful Na2 SO4, NaCl, Nal, NaBr, NaNO3, and of the potassium salts K2SO4, KC1, KNO3. The rhythmical move- ment of the whole medusa is controlled by the marginal sense-organs.

The action of the cations of the sea-water upon Rhizostoma appear, from Bethe's work, to be similar to their effect upon Cassiopea, and I believe that the two medusae are controlled in the same manner. (See Cassiopea xamachana.)

I think, therefore, that Bethe is mistaken in concluding that potassium and calcium stimulate pulsation. It is true in both Rhizostoma and Cassiopea that pulsation endures longer in NaCl + KCl or in NaCl + CaCl2 than in pure NaCl, but its rate is slower. Indeed the rate of pulsation in NaCl is so abnormally rapid that the medusa soon comes to rest exhausted, and this exhaustion is partially prevented by the subduing effects of K or Ca and thus the pulsation endures longer but at a slower rate. The apparent stimulation upon adding calcium in excess is not due to the direct effect of the Ca, but to the fact that Ca counteracts the stupefying effects of Mg, thus permitting the sodium to act more effectively as a stimulant. Thus the sea-water is a balanced fluid, the stimulating effect of the Na cation being offset by the stupefy- ing effects of Mg, K, and Ca.

Hargitt, 1904, has studied regeneration in R. pulmo, and he finds that it possesses a moderate capacity, in confinement, for replacing lost rhopalia. Often 2 rhopalia regenerate in the place of the one which has been cut away. The medusa has but little power to regenerate mouth-arms or gastric lobes.

Hesse, 1895, has made an elaborate study of the histology of the marginal sense-organs and of the nervous network of the subumbrella. Definite strands of nerve-fibers extend radially inward from the marginal sense-organs under the subumbrella epithelium. These radial-fibers bend circumferentially at the zone of the ring-canal, forming a wide ring-like band of nerve-fibers on the inner side of (centripetal to) the ring-canal. These nerve-fibers arise from bipolar ganglia which are found in considerable numbers in the ectoderm along the lines of the radial-canals which extend to the sense-organs. The bipolar ganglia are derived from ectodermal cells of the subumbrella.

The ectodermal cells of the marginal sense-organs bear cilia, and some of them are sensory while others are supporting cells. The sensory pit on the exumbrella side of the sense-club is also lined with a ciliated, ectodermal epithelium containing sensory and support- ing cells, and also ganglion cells which send numerous nerve-fibers downward through the gelatinous substance into the entodermal core of the sense-club, where they form a felting of fibers extending into the region of the entodermal concretions.

The inner sensory pit on the subumbrella side of the sense-club is also lined with an epithelium similar to that of the exumbrella pit, and it also sends nerve-fibers into the sense- club. The sensory and ganglion cells of these 2 pits and of the sense-club constitute the central nervous system of the medusa.

RHI/USTiiM.K — HIIIZIISTUMA. 703

Rhizostoma pulrao var. lutea Eschscholtz.

Orithvia lutea, Qtiov tT GAIMARD, 1827, Anna), dc^ Sn. Nat., Zool., tome 10, p. 175, planche 48, fig. I. Rhizostoma lutea, ESCHSCHOLTZ, 1829, Syst. dor Acalephen, p. 51. Pilema stylonectes, HAECKF.L, 1880, Syst. der Mrdusen, p. 595.

Rhizostoma hileum, VANHUFFF.N, 1888, Bibliotheca Zoologica, Hil. I, Heft. ;, p. 4;. <;K>\M it t R UNO NOLL, 1876, Abhandl. Senckcnberg Naturforsch. Gesell., Bd. 10, p. 42, taf. 8.

See the tabular synopsis of species of Rlitzostomn.

This medusa, from the Straits of Gibraltar, is intermediate in most of its characters between R. pultun of the Mediterranean and R. octopus of the Atlantic coasts of Europe. Indeed the 3 forms are so closely related that we may consider them to be local varieties one of another. R. lutea is distinguished chiefly by its very long, terminal appendages on the mouth-arms.

Rhizostoma pulmo var. octopus Oken.

I 'nil a m, ir inn, fir., octopedalis, BORLASK, 1758, Nat. Hist, of Cornwall, p. 258, plate 25, figs. 15-17.

Medusa octopus, LINNE (Gmelin), 1788, Systema Natura-, Ed. 15, Pars. 6, p. 3157.

Medusa bleu, CI'VIF.R, 1799, Journal de Pli\^ii|Uii, C'himir, d'Hi^t. N.u. ct drs Arts, Paris, form- 49, p. 437, I planche.

Cassiopea borlasea+ Rhizostoma curieri, PERON FT LIM n K, 1809, Annal. du Mus. Hist. Nat. Paris, ionic 14, pp. 357, 362.

Cassiopea lunulata, ESCHSCHOLTZ, 1829, Syst. di-r Acah-phcn, p. 44.

Rhvzostoma octopus, OKEN, 1835, Allgcmcine Naturgesch., Bd. 5, p. 218.

Cassiopca angliea+C. rhizoslomoidea+ Rhizostoma sepioidcs, TILESIUS, 1829, Nova Acta Acad. Cur., Leop. C., tome 15, pp. 273, 283:, tab. 71.

Rhizostoma cocrultutn, CI'VIER, 1817, Regnc Animal., tome 4, p. 57.

Holigocladodes lunulatus, ACASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 155.

Pilema octopus, HAF.CKEL, 1880, Syst. der Meduscn, p. 593 (list of authors).

Rhizostoma octopus, VANHOFFKN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, p. 43; 1906, Nordisches Plankton Acraspcde Medus., Nr. II, p.63,fign. 33,34; 1908, deutsche Siidpolar Expcd., 1 901 -03, Bd. lo, Zool.2, pp. 28, 47. — DAHL, 1893, Kommiss. zur wissenschaft. Untersuch. deutsch, Mcerc Kiel, Bcr. 6, p. 172. — BROWNE, 1905, Proc. Roy. Soc. Edinburgh, vol. 15, p. 776.

This form is closely allied to R. pulmo of the Mediterranean, but it ranges into the cold waters of the Atlantic coasts of Europe, being found off the shores ot France, England, Scotland, Belgium, Holland, and Germany. Mature individuals occur in great swarms in September and October and are often cast ashore in vast numbers. The medusa differs from R. pulmo in having 96 to 112 marginal lappets instead of 80. The lappets are more pointed than in R. pulmo. The simple, upper part of the arm is shorter than the lower, ^-winged part, whereas in the typical R. pulmo the reverse is usually the case. The terminal clubs are widest near their outer ends, whereas in R. pulmo they are widest near their bases. In other respects it appears to be identical with R. pulmo.

Vanhoffen, 1906, describes the young ephyra, 3 mm. wide, in the stage wherein the 4 rays of the cruciform, central mouth are beginning to fork at their outer ends. There are 4 small

o o

clusters of gastric cirri. 16 radial-canals. The 8 rhopalar radial-canals extend to the marginal sense-clubs and the 8 adradial canals end in the ring-canal, which is at a considerable distance inward from the bell-margin. This ephyra is thus similar in all respects to that ot R. pulmo. It is somewhat remarkable that R. octopus is not found among the Azores, Canaries, or other island groups of the Atlantic. Borlase states that in 1758 it was sometimes eaten by man in Cornwall.

Rhizostoma pulmo var. corona Eschscholtz.

Mfdtistt corona, FORSKAL, 1775, Descript. Anim. Ttin. Orient., p. 107.

Rhizostoma corona, ESCHSCHOI.TZ, 1829, Svst. der Acal., p. 52.— VANHIIFFEN, 1888, Bibliothcca 7x»logic.i, Bd. I, H.-ft. ',. p. 43.

Rhizostoma cuvieri, EHRF.NBERG, 1835, Abhandl. Berlin Acad., p. 184.

Pilrma corona, HAECKF.L, 1880, Syst. der Meduscn, p. 594.

See synoptic table of the species of Rhizostoma.

This imperfectly known Red Sea medusa appears to be closely related to R. pulmo of the Mediterranean, but is said to be distinguished by having 140 to 180 marginal lappus. instead of 80 as in R. pulmo.

Rhizostoma pulmo var. capensis Lesson.

Cephea capensis, QUOY IT GAIMARD, 1824, Voyage de Vl'ranie, p. 568, planche 84, fig. 9.

Rhizostoma capensis, LESSON, 1843, Hist. Zooph. Acaiephes, p. 417.

Pilema capense, HAECKEL, E., 1880, Syst. der Mt-.lu-i-n, p. 64^.

Rhizostoma capense, VANHOFFEN, 1888, Bibliothcca Zoologica, Bd. i, Heft. 3, p. 43.

704 MEDUSAE OF THE WORLD.

Ouoy and Gaimard give an artistic, but evidently inaccurate, figure of this medusa, and they fail to describe it. Their record is only interesting in that it indicates that a Rhizostoma is found in the South Atlantic.

This form is from Table Bay, coast of South Africa, in March. It may be identical with R. octopus or R. pulmo. Quoy and Gaimard's figure shows an evenly rounded, oval bell, higher than a hemisphere, with smooth or finely granular surface and with numerous rounded lappets, as in R. pulmo. The lower arms are apparently longer than the upper, as in R. octopus, and the terminal clubs are bluntly pointed, taper from base to tip, and are about as long as the upper arms.

The colors are as in R. pulmo, but the bell and terminal clubs appear to be of a deeper blue. Size ( ? ) Number of lappets ( ? ) The medusa has not been seen since the days of Ouoy and Gaimard.

Genus RHOPILEMA Haeckel, 1880.

Rhopilema, HAECKEL, 1880, Syst. dcr Medusen, p. 596.— MAAS, O., 1903, Scyphomedusen der Siboga Expedition, Monog. u, p. 71.— CLAUS, 1883, Organisation und Entwick. Medusen, p. 60.— VON LENDENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 291.— KISHINOUYE, 1890, 91, Zool. Magazine, Tokyo, vol. 2, p. 47; vol. 3, p. 53; 1899, Zoolog. Jahr- biich., Abth. Syst., Bd. 12, p. 205.

Rhizostoma (in part), VANHOFFEN, 1888, Bibliothcca Zoologica, Bd. I, Heft. 3, pp. 31, 43.

Neclopilema, FEWKES, 1887, American Journ. Sci., ser. 3, vol. 33, p. 120.

GENERIC CHARACTERS.

Rhizostomata scapulata with 8 separated, 3-winged, adradial mouth-arms which bear numerous filaments or club-shaped appendages.

The central stomach gives rise to 1 6 radial-canals placed in intercommunication by a network of anastomosing vessels. A ring-canal may or may not be present.

This genus is closely related to Rhizostoma (Pilema of Haeckel), but in Rhizostoma a single club-shaped appendage arises from the lower end of each of the 8 mouth-arms and there are no other clubs or filaments; while in Rhopilema there are many appendages upon each mouth-arm. The type species is R. rhopalophora of the Indian Ocean, and the same medusa appears to have been described by Kishinouye from Japan. " Nectopilema" ot Fewkes is identical with Rhopilema.

The edible medusse of China and Japan belong to the genus Rhopilema.

The terminal clubs upon the mouth-arms of Rhizostoma are merely the downward, mouth- free extension of the axial shaft of each arm. These terminal clubs are triangular in cross- section, as are the mouth-arms themselves, and they contain a continuation of the axial-canal of the arm. They are not homologous with the vesicular, club-shaped mouth-filaments of Rhopilema.

Rhopilema esculenta Kishinouye.

Rhopilema sp., KISHINOUYE, 1890, Zool. Magazine, Tokyo, vol. 2, p. 47, plate 2.

Rhopilema esculenta, KISHINOUYE, 1891, Zool. Magazine, Tokyo, vol. 3, p. 53; 1899, Zoolog. Jahrbucher, Bd. 12, Abth. Syst.,

p. 205, taf. 13, fign. 1-5. ( ?) Rhopilema rhopalophora, HAECKEL, 1880, Syst. der Medusen, p. 596.

The umbrella is more than 450 mm. wide, about 330 mm. high when contracted, but nearly hemispherical when expanded. It is about 50 mm. thick at the center, but gradually becomes thin toward the margin. Exumbrella smooth, but the marginal lobes are furrowed with numerous, minute, longitudinal (radial) grooves. 8 marginal sense-organs, each with an exumbrella sensory pit which displays radiating furrows in its floor. In each octant of the margin there are 14 to 20 oval, velar lappets between 2 very small, lanceolate, ocular lappets. The ocular lappets are only about one-fourth as long and as wide as the velar lappets.

In the subumbrella the circular muscles are well developed and unitary, and the coronal furrow is not distinct. The arm-disk is very thick and prismatic, about one-third as wide as the bell-diameter and somewhat longer than wide. The 4 oral pillars are quadrate and the 4 subgenital ostia are somewhat heart-shaped and as wide as the pillars. There is a rough, prickly protuberance upon the floor of the subumbrella opposite the opening of each sub- genital ostium. Altogether, therefore, there are 4 of these protuberances alternating with the 4

KimnSToM i: KHOI'II.I.M \.

arm-disk pillars, and thus interradial in position. 4 separate genital cavities. 8 pairs (16) simitar-shaped scapulets arise troin the adradial sides of the arm-disk. Their upper sides are convex and hear trilled mouths and numerous, hollow filaments which are about two-thirds as long as the scapulets themselves. The lower sides of the scapulets are concave and desoid ot mouth-openings or filaments.

The 8 adradial mouth-arms are stout, triangular, and pyramidal, and exclusive of then appendages they are about two-thirds as long as the diameter of the umbrella. The upper pans of these arms are coalesced with each other along halt then lengths. These upper parts

.iii.kilUi.l * . ' ,i

. V« ' , ) \ '

I ml !;,.;• .i./_"

FIG. 423. — Rhopile ma t iculenia. After Kishmomv, in Zoolog. Jahrb., Abth. Syst., Bd. u. A and B, side and front views of mouth-arms. C, sagittal section of medusa. D, oral view of arm E, rhopalium. F, subumbrella showing canal-system (above) and muscular sectors (below).

of the arms are free of mouths and are about as long as the scapulets, while the lower parts are twice as long as the upper and bear numerous, trilled mouths and more than 100 appendages. There are 2 kinds of appendages — filamentous and fusiform. The fusiform appendages are longer than the filaments and may be three-fourths as long as the diameter ot the umbrella, the 5 longest being found at the center and I at each perradial angle of the arm-disk. The filaments are much more numerous than the tusitorm appendages. 1 here are no definite terminal clubs at the lower ends of the mouth-arms.

The central stomach gives rise to 16 radial-canals, 4 perradial, 4 interradial, and N adradial. These canals extend to the bell-margin and are connected one with anotlui h\ means of an indistinct ring-canal which is about midway between the margin and the periphery

706 MEDUSAE OF THE WORLD.

of the stomach. On its inner side the ring-canal gives rise to an anastomosing network of vessels which fuse with the perradial and interradial canals, but not with the adradial. On its outer side the ring-canal gives off another network which fuses with all 16 radial-canals.

4 main canals arise from the lower part of the stomach in the 4 principal radii. These main canals fork and each fork extends down one of the 8 adradial mouth-arms, where they branch many times and go to the numerous frilled mouths.

The color of the medusa is usually blue, but occasionally dark-red. The mouth-frills are brown and the mouth-arm appendages are milky-white, or nearly transparent. The gonads are yellow, the male being lighter in color than the female.

This medusa is abundant in the Inland Sea of Japan, and is also found off the coast of China.

It is the custom in Japan to preserve it with a mixture of alum and salt or between the steamed leaves of a kind of oak. It is then soaked in water, flavored with condiments, and when so prepared constitutes an agreeable food.

Rhopilema rhopalophora Haeckel, from the Indian Ocean east of Madagascar, is closely allied to, if not identical with, this Japanese medusa, but it is said to have a large, terminal club at the end of each arm. This club is fusiform, triangular in cross-section, and as long as the whole lower-arm itself. There are 144 lappets, the velar ones being rectangular, and the bell is 100 mm. wide and hemispherical. In other respects it appears to be similar to Kishinouye's medusa, although Haeckel's description is too brief to be satisfactory.

Rhopilema hispidum Maas.

( ?) Piltma clavigera, HAECKEL, 1880, Syst. der Medusen, p. 595.

Rhizosloma hispidum, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. I, Heft. 3, pp. 32, 43, taf. 5, fign. I, 2.

Rhopilema verrucosa, KISHINOUYE, 1899, Zoolog. Jahrbiicher, Bd. 12, p. 208, I fig.

Rhopilema hhpidum, MAAS, 1903, Scyphomedusen der Siboga Expedition, Monog. n, p. 73, taf. 9, fign. 78-81.

Bell hemispherical or higher than a hemisphere, and may become about 250 to 340 mm. in diame'.er. Walls very thin; the exumbrella is thickly besprinkled with small, sharp-pointed, conical projections. The 8 marginal sense-clubs have no ocelli, but above each is a large, sensory pit with radiating furrows. 80 marginal lappets. The 8 sense-organs are each flanked by a pair of very small, narrow, lanceolate lappets and there are typically 8 velar lappets in each octant of the bell-margin; these velar lappets are oblong, rounded, and 3 times as long and 5 limes as wide as the ocular lappets.

The arm-disk is of the usual 8-sided form. The 4 interradial subgemtal ostia are, according to Maas, not quite so wide as the perradial columns of the arm-disk between them; but according to Kishmouye the subgemtal ostia in his "Rhopilema verrucosa," which appears to be identical with R. hispidum, are 3 times as wide as the perradial columns. The 4 genital cavities are only partially and irregularly fused and do not form a unitary genual space, as in Mastigias and Crambessa, nor are they completely separated into 4 cavities, as in Cassiopea (see Maas, 1903). The 8 mouth-arms are two-thirds as long as the diameter of the umbrella. They are fused one with another in the upper thirds of their lengths and are free in their lower two-thirds. There are 16 scapulets, 2 of which arise from the abaxial (outer) side of each of the 8 upper arms. Each scapulet is simitar-shaped and forked at its outer end, and is about half as long as the radius of the umbrella. There are frilled mouths and elongate filiform appendages upon the upper side of each scapulet.

The lower arms are 3-winged or Y-shaped in cross-section, one wing being inward and axial, the other wings being lateral and directed outwardly. Each of these lateral wings is of the shape of an equilateral triangle, and there are 4 elongate, sharp-pointed projections from the abaxial angle of each wing. The pointed lowermost end of the lower arm terminates in a large, club-shaped appendage, with a faceted, swollen end. This appendage is about as long as the upper arm and there are other much swollen, club-shaped appendages which arise between the frilled mouths of the 3 wings of each of the lower arms.

The canal-system of the umbrella consists of 16 radial-canals, 4 perradial, 4 interradial, and 8 adradial, the adradial ones being nearer to the perradial than to the interradial canals. All of the canals extend quite to the bell-margin, and all give off side branches which form an anastomosing network. A definite ring-canal is not present. The circular muscle-system

PLATE 74.

Fig. i. Rhopilema vernllii, mature medusa, 0.5 natural size. Bell shown expanded. When in systole it is higher than a hemisphere. Off Middletown, Pamlico Sound, North Carolina, November 16, 1904.

Fig. i'. Rhopilema verr illii. Marginal sense-organ seen from the exumbrella side, showing the sensory pit in the exumbrella above the club. The sensory-mass is orange. There is no ocellus.

Fig. 2. Crambione cookii, O.66 natural size. Agassiz Expedition to the Great Barrier Reef, off Cooktown, Queensland, Australia; May 4, 1896.

For figure 2 see page 677. Drawn from life, by the author.

PLATE 74

UHIX.OSTIIM.K — KHoril.KM \. 7l 17

of the subumbrella consists of 16 triangular areas which alternate with and art- widely sepaiatcd by the 16 radial-canals.

This medusa was described by Yanhoffen from Ilon»kon», China. and later In M.I.IS from the Malay Archipelago. It appears to In- identical with A" . Kishinoiue. fiom

Japan. R. hispiditm is possibly identical with l'il,-m,i J,i\-ig,-r,i Haeckel; hut in HacckeTs medusa there are only 4* marginal lappets when the disk is 90 mm. wide, whereas in A?. hispidum ot the same width there are 80 marginal lappets. The granular projections upon the exumhrella in Haeckel's medusa are bluntly rounded, \\heieas in A'. Inspidum ihcv aic sharp and thorn-shaped. The terminal appendages of the mouth-arms appear to he some- what longer in Haeckel's medusa than in K. hispiJuni. I laeckel desciihcs "I'll, m,i ,l,r, from a single alcoholic specimen from 1 lon^konu, China.

Rhopilema verrillii.

Plate 74, figs, i, i'. Nrctopitema vtrril/ii, FEWKES, 1887, American Journ. Sci., ser. 3, vol. 33, p. 119, plate 4.

The disk is tully 350 mm. in diameter, hemispherical in contraction, but slightly Hattei than a hemisphere when expanded. The gelatinous substance is thick and rigid. The cen- ter ot the exumhrella is smooth, hut over the lappets there are many shallow furious and the surface near the margin resembles sand-paper, being covered with numerous minm vations. There are 8 marginal sense-organs, each of which contains a terminal, entodeiin.il concretion-mass oi red pigment granules. There is a simple, exumbrella sensory pit without furrows; 64 marginal lappets. There are 6 large, oval lappets in each octant of the margin of the disk, together with 2 small, oval lappets adjacent to the sense organs.

The arm-disk is cruciform and about half as wide as the bell, and the 4 perradial col- umns are only three-fifths as wide as the heart-shaped, subgenital ostia. 8 short, tounh, gelatinous, lower mouth-arms, which arise from the arm-disk, are each about 180 mm. lono and Y-shaped in cross-section below. They branch sparingly and the \erv numerous mouths are found upon their lower and inner sides, in furrows bordered by numerous, small, wa\in<i cirri. There are about 25 to 60 blunt, translucent spindle-shaped appendages, \\luch anse from the lower sides of the mouth-arms, and are besprinkled with wart-like clustets ot nematocysts. '1 he largest filaments arise from the principal crotches ot the mouth-arms.

A pair of short flapper-like, lateral scapulets arise from the outer side ot each of the 8 mouth-arms near its base, the mouth-openings of which are confined to their upper < and connect by a main duct in each scapulet with the axial-canal of the arm to which the\ ,iu attached. "I here are no appendages upon the scapulets. 4 short, gelatinous, perradial columns connect the arm-disk with the subumbrella. There are 4 deep, heart-shaped clefts 01 genital ostia between these 4 columns, hut the bottom of each cleft is bridged o\er by a d< membrane. The 4 separate gonads develop within this membrane and the stomach is bor- dered on the sides by the 4 stout, perradial columns and the 4 inter/radial memhiancs. The 4 genital sacs are separated one from another; indeed the gonads are somewhat protru- sive in old medusa?.

There is a blunt wart-like papilla upon the subumbrella surface at a short distance beyond the opening of each genital ostium, and this partially constricts the opening. gi\ing it a heart-shaped outline. The circular muscles of the subumbrella are \ei\ poweitul, but are almost interrupted in the radii of the 16 radial-canals in old medusa- although thev aie entire near the margin in young animals. Thus in old medusae there are !'• paniallv isolated arcades of circular muscles as in Rhizrjstvtuti pulmo. Tlu-ie arc no i.ulial muscles.

The stomach is wide and crucifoim, and corresponds m outline with the crucitoim arm disk under which it lies. Its exumbrella roof is plane, but the suhumbiella floor dips downward into the center of the arm-disk, and 4 open, perradial. gutter-like iun»\\s extend from this central depression down the center ot each perradial column to the outei edm "I the stomach. 4 perradial ducts arise from the depressed center of the stomach at the middle of the arm-disk, and these soon bifurcate giving 8 adradial ducts \\hnh t \tend do\\ n each of the 8 mouth-arms giving offside branches to the numerous mouths.

708

MEDUSAE OF THE WORLD.

The axial ducts of the 16 small, flapper-like, lateral scapulets connect directly with the axial duct of the arm to which they are attached. The large, central stomach gives rise to 16 main radial-canals which extend outward to the 8 sense-organs and to intermediate points on the bell-margin. These 16 main radial-canals give rise to numerous side branches which anastomose in a network of vessels as in Rhizostoma pulmo. There is no definite ring- canal in the adult.

The gelatinous substance of the medusa is translucent, dull, milky-yellow. The mouths are rich yellow with chocolate-red blotches of pigment scattered at intervals at the bases of the cirri. The ring-muscles of the subumbrella are a decided yellow, and according to Fewkes the radial-canals are chocolate or rich chestnut in color. In the specimens studied by me, however, they were yellow. The gonads are dull milky-yellow. There are numerous, small, gastric cirri upon the gonads.

FIG. 424. — Rhopilema verrillii. Drawn^by the author from a specimen obtained by Professor Verrill at Outer Island near Branford, Connecticut.

Drawing one-half natural size. 6 of the mouth-arms are cut off close to their bases, and the scapulets are cut off from 4 of them in order to show 2 of the subgenital ostia. The muscular arcades are shown in one-half of the subumbrella and the canal-system in the other half. Thus in old medusa? there are 16 partially isolated arcades of circular muscles as in Rhizostoma pulmo. There are no radial muscles.

This rare medusa was first found by Prof. A. E. Verrill, in 1886, in New Haven Harbor, Connecticut, during September. In 1889, Professor Verrill again found it in considerable numbers among the Thimble Islands about 10 miles east of New Haven, in Long Island Sound, where they were common in August and September. They then disappeared, but were again found at the Thimble Islands during the summer and autumn of 1903, and again in Branford Harbor, Connecticut, in September and October, 1909. I secured the specimen figured on plate 74 at Middleton, Pamhco Sound, North Carolina, in November,

RHIZOSTOM.E — RHOPILEMA, El'PIJ.KMA, STOMOLOPHUS. 709

1904, where it was swimming near the surface on a calm morning. The fishermen informed me that it is seen quite frequently in Pamlico Sound in autumn. I helieve, there- fore, that it is a southern form which occasionally establishes itself in Long Island Sound. The following are the dimensions in mm. of a specimen of Rhopilema verrillii found by Professor Vernll at Outer Island, near Brantord, Connecticut, in Long Island Sound, on September 12, 1909.

Diameter of contracted bell, 218. Width of largest velar lappets, 11.

Diameter of fully-expanded bell, 268. Length of largest velar lappets, 12.5.

Perradial diameter of arm-disk, 135. I^enyth of scapulets, 36.

Interradial diameter of arm-disk, 76. Length of mouth-bearing part of scapulets, 35.

Width of each perradial column of arm-disk, 33. Length of lower arms, 65.

Circumferential width of subgenita! ostium, 49 Width at widest distal part of lower arms, 54±.

Radial width of subgenital ostium, 27. Width of lower arms at points of origin from arm-disk,

Width of zone of circular muscles, 54. 26 to 32.

Width of ocular lappets, 3. Length of longest mouth-arm appendages, 26.

Length of ocular lappets, 5. 5.

Genus EUPILEMA Haeckel, 1880. Eupilema, HAECKEL, 1880, Syst. der Medusen, p. 590.— VANHOFFEN, 1888, Bibliothcca Zoologica, Bd. I, Heft. 3, p. 43.

The type species is Euphilema scapulare Haeckel, from the Malay Archipelago. Cyanea rhtzostonifi Brandt, 1838, may be of the same genus, but is too imperfectly described to be determined.

GENERIC CHARACTERS.

Rhizostomata scapulata with 8 free, 3-winged mouth-arms, without filaments, clubs, or other appendages. 16 radial-canals all connected by an anastomosing network of vessels in the outer parts of the subumbrella.

This genus is closely related to Rhizostoma, but has no mouth-arm appendages.

Eupilema scapulare Haeckel. Eupilrma scapulare, HAECKEL, 1880, Syst. der Medusen, pp. 582, 590. — VANHOFFF.N, 1888, Biblio. Zool., Bd. I, Heft. 3, p. 43.

Bell 150 mm. wide, 50 mm. high, hat-shaped with rounded dome. 8 rhopalia, 144. lappets. In each octant 8 pairs ot long, narrow, rectangular, projecting, velar lappets, between 2 small, oval, ocular lappets. Mouth-arms not quite as long as bell-radius. Scapulets simitar-shaped, as long as free, upper part of arm. 17 radial-canals all connected by an anastomosing network of vessels which extend inward to the zone of the bases of the ami-disk pillars. The form of the scapulets shows that they are only the secondarily separated, uppermost lappets of the dorsal wings ot the mouth-arms. Color (?) Sunda Archipelago, Sumatra.

Very briefly described from a preserved specimen by Haeckel.

Genus STOMOLOPHTJS L. Agassiz.

Siomolophus, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 138, 151. — ACASSIZ, A., 1865, North American Acal., p. 40. — CLAUS, 1883, Organisation und Entwick. Medusen, p. 60. — VON LENDENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 292. — VANHOFFEN, 1898, Bibliothcca Zoologica, Bd. i, Heft. 3, pp. 30, 42. — MAAS, 1903, Scyphomeduscn der Siboga Eiped., Monog. n, p. 80.

Brachiolophus + Stomolophus, HAECKEL, 1880, Syst. der Medusen, pp. 597, 598.

The type species is S. meleagris L. Agassiz, which ranges from South America to the mouth of Chesapeake Bay, United States, and is apparently found also on the Pacific side of the Isthmus of Panama.

GENERIC CHARACTERS.

Rhizostomata scapulata with a central mouth-opening. With a well-developed, tube-like manuhnum formed by the fusion ot the lateral edges of the 8 primitive mouth-arms. Only the extreme ends of the mouth-arms are free and they branch complexly. 8 pairs of scapulets. 4 separate invaginated gonads. The central stomach gives rise to 16 radial-canals, which are all connected by a marginal network of anastomosing vessels. 8 marginal sense-organs.

Brachiolophus Haeckel is only a young stage of Stomolophus.

710 MEDUSAE OF THE WORLD.

Stomolophus meleagris L. Agassiz. Plates 75 and 76, figs. 1-3.

Cep]iea rhizosloma, GIBBES, 1847, (non Lamarck) Fauna of South Carolina.

Stotnoloplius meleagris, AGASSIZ, L., 1862, Cont. Nat. Hist. U. S., vol. 4, pp. 138, 151; Ibid., 1860, vol. 3, plate 14, figs. 1-8. —

AGASSIZ, A., 1865, North Amer. Acalephx, p. 40.

Slonwlophus meleagris+S. agaricus ?, HAECKEL, E., 1880, Syst. der Medusen, p. 599. Stomolophus chunii, VANHOFFEN, E., 1888, Bibliotheca Zoologica, Bj. i, Heft. 3, pp. 31, 42, taf. 3, fign. 4, 5; taf. 4, fig. I. —

TRINCI, G., 1906, Ajinuar Mus. Zool. Napoli, ser. 2, vol. 2, No. 9, pp. 1-4.

Bell about 180 mm. in diameter, half-egg-shaped, higher than a hemisphere, the gelatinous substance thick and rigid; no marginal tentacles; 8 marginal sense-organs, 4 radial and 4 interradial. Each sense-club is deeply set within a niche between the ocular lappets and is protected above by a partial web between the lappets. Sense-club hollow and spindle-shaped, terminating in a knob-like end which contains an entodermal mass of deeply pigmented concretions. A deep, j-sided, furrowed pit projects inward from the surface of the exumbrella just above the base of each sense-club (see [c] fig. 2'", plate 75). About 128 marginal lappets, 16 in each octant, those flanking the sense-organs being about 3 times as long as the others. The velar lappets have rounded edges, but the ocular lappets are longer and sharp-pointed.

A rigid, thick-walled mouth-tube, or manubrium, projects downward from the center of the subumbrella and extends 40 to 50 mm. beyond level of bell-margin. This manubrium- hke tube is formed by the lateral coalescence of the 8 adradial mouth-arms, which are fused along their adjacent sides, their extreme ends only being free. These free ends of the mouth- arms bifurcate and flare outward at lower end of manubrium. A deep groove, or gutter, extends along the ventral side of each of the 8 mouth-arms and branches dichotomously twice and extends outward over the lower sides of the 16 free ends of, the mouth-arms. The free edges of this branching groove are complexly branched and folded and are lined by a row of numerous small knobbed tentacles', which move constantly in such manner as to drive food particles into the mouth-grooves. In addition to the central mouth, there are numerous slit- like lateral mouths which are situated upon 16 knife-blade shaped scapulets attached to the upper part of, and occupying more than half of the length of, the manubrium. The free edges of these lateral mouths are complexly crenulated and lined with small, incessantly waving tentacles exactly as are the mouth-grooves at the free extremity of the manubrium (fig. 2, plate 76). The 8 main mouth-grooves of the manubrium lead into a 4-cornered, central oesophagus which extends upward into the wide, central stomach. 16 lateral branches, 4 from each side of this four-cornered oesophagus, extend outward to the slit-like mouths in the 16 scapulets. These radiating tubes arise from the oesophagus near the level of the upper parts of the scapulets. The central stomach is wide and lenticular, and occupies the midst of the umbrella. It gives rise peripherally to 16 radial-canals which in their outer halves give off many side branches which in turn form an anastomosing network placing all of the radial-canals in connection one with another, as in the genus Rhizostoma. No ring- canal.

There are 4 deep, cylindrical subgenital pits, and a blunt papilla is found on the sub- umbrella surface just beyond the opening of each genital ostium. The gonads are found in 4 folded regions in the wall of the subumbrella at the bottom of the subgenital pits. There are 16 semi-elliptical areas of circular muscles in the subumbrella, 2 between each succes- sive pair of sense-organs. Alternating with the circular-muscle areas there are 16 narrow, triangular strands of weakly developed radial-muscle-fibers, the broad end of each triangle abutting against the side of the manubrium, and the narrow, pointed end being directed outward. 8 of these occupy the radii of the marginal sense-organs and 8 are intermediate in position. The bell-margin pulsates incessantly with remarkable strength and rapidity.

The gelatinous substance of the bell is of a milky bluish or yellowish color and the ento- dermal parts are dull yellow. The surface of the exumbrella is reticulated with brown pigment which is especially dense near the margin. There are numerous white or yellowish spots in this brown marginal zone. The mouth-frills are brownish-pink.

young medusa. — I have captured an immature medusa of this species in which the bell was 3 mm. in diameter and the entire animal 5 mm. in length (fig. 3, plate 75). The bell was flatter than a hemisphere and the surface of the exumbrella was covered with wart-like clusters of nematocysts, among which there were numerous, brown-colored pigment cells.

PLATE 75. All figures are of Stomoloplius meleagris.

Fig. i. Mature medusa, 0.66 natural size. In the ocean off Fernandina,

Florida, January 3, 1905. Fig. 2. Young medusa, 1.5 times natural size. Charleston Harbor, South

Carolina, August 28, 1897.

Fig. 2'. Sagittal section of the medusa shown in figure 2. Fig. 2". Cross-section of the fused mouth-arms of the medusa shown in

figure 2, cut at the level of the 16 scapulets. Fig. 2'". Marginal sense-organ of the medusa shown in figure 2, showing

the exumbrella pit above the sense-organ. There is no ocellus. Fig. 3. Young medusa, 5.5 mm. long and 3 mm. in diameter, showing the

lateral mouths (scapulet mouths) beginning to break through the

walls of the primitive oesophagus. Charleston Harbor, South

Carolina, September 9, 1898. An oral view of this medusa is

shown in figure I, plate 76.

Drawn from life, by the author.

MAYER

PLATE 75

PLATE 76. All figures are of Stomolophus meleagris.

Fig. i. Oral view of a young medusa 3 mm. in diameter. A side view of this medusa is shown in figure 3, plate 75.

Fig. 2. Sagittal interradial section of mature medusa shown in figure I, plate 74. Also cross-sections of the mouth-arm-tube at three different levels, g, gonad; p, subumbrella papilla in the radius of the sub- genital pit; S, stomach cavity; sg, subgenital pit.

Fig. 3. Oral view of a quadrant of subumbrella, omitting the mouth-parts. The sector AB, shows the canal-system of the subumbrella, and BC two of the 16 sectors of circular muscles.

Drawn from life, by the author.

MAYER

PLATE 76

•

o

RHIZOSTOM.E — STO.MOLOPH r S. 711

There were 8 marginal sense-organs and 48 marginal lappets (fig. i, plate 76). The lappets flanking the sense-organs were about twice as long as the others. The ocular lappets were, however, simple while the others were bifurcated and evidently in process of division. The central mouth was situated at the extremity of a long 4-cornered proboscis which possessed 4 bifurcated lips. The free edges of these lips were lined by a row of short, slender, knobbed tentacles which maintained a constant motion. In addition to the principal or terminal mouth there were 8 small, tube-like, lateral mouths arranged in 4 pairs, the beginnings of the scapulets. These mouths arose from the sides of the manubrium near its base and were interradial in position (/. <•., 90° from the radii of the 4 principal lips), and in addition to these lateral mouths there were 4 pans of hernia-like protections upon the surface of the manubrium. These pro- jections alternated in position with the already functional, lateral mouths, and would no doubt soon ha\e broken through and formed another set of such mouths (fig. i, plate 76). The functional mouths were each surrounded by 8 tentacles which wrere similar in structure to the tentacles lining the free edges of the principal mouth.

The medusa was quite transparent except for a trace of brown pigment in the ectoderm of the exumbrella and the dark-red pigment of the sense-organs.

I found it in Charleston Harbor, South Carolina, on September 9, 1898.

The resemblance between this young rhizostomous medusa and the adult condition in the Semaeostomeae is very striking. The terminal mouth was used, indeed, for the capture of food, an operation which was facilitated not only by the flexibility of the lips but also by the incessant motion of the tentacles.

This species is very common along the sandy coasts of North and South Carolina and Georgia. In April, 1910, mature medusae were abundant at Tortugas, Florida. It does not extend north of the mouth of Chesapeake Bay. It is found along the northern coast of South America, and at many places in the Gulf of Mexico, and I believe it to be identical with .V. fliiinii Vanhiiffen, from the Bay of Panama on the Pacific side of the Isthmus. It often occurs in vast swarms, occupying an area which is sometimes over 100 miles in length. Mature individuals are abundant in winter and spring off the coast from Florida to South Carolina. It is not often seen in brackish harbors, but is practically confined to pure ocean water off the coast. At most it enters only the mouths of harbors.

I can see no difference between 5. chunn Vanhoffen and S. mcleagns. S. cliunii is described as being only 90 mm. wide and with only 112 marginal lappets. In all respects it resembles a half-grown S. meleagris. Indeed, Trinci, 1906, records S. chunii from the Gulf of Paria between Trinidad and Venezuela, Atlantic coast of South America, and it appears, therefore, that "S. chunn" must occur on both Atlantic and Pacific sides of the Isthmus of Panama. It is probable that the medusa has remained unchanged since the closure of the Isthmus in Mesozoic times.

Haeckel's Brachiolophus collans is only a younger stage of the same medusa with a bell 80 mm. wide and with 80 marginal lappets. It is described from the Galapagos Islands.

Stomolophus meleagris var. fritillaria.

Stomotoptius friiillaria, HAECKKL, 1880, Syst. der Medusen, p. 598, taf. 35, fign. 1-9. — VON LENDENFELD, 1884, Proc. Linneao Soc. New South Wales, vol. 9, p. 292. — VANHOFFEN, 1888, Bibliotheca Zoologica, BJ. i, Heft, j, pp. 31, 42.

This form appears to be smaller than S. meleagris, the bell being only about 80 mm. in diameter and (>o mm. in height. The marginal lappets are more numerous, being 208 in number. The "manubrium" or fused tube of mouth-arms extends only about one-fourth the bell-height beyond the level of the margin, instead of about one-third the bell-height, as in .S1. iiii-lt-/i^ris. This medusa is found at Suranim on the Atlantic coast of South America. Color(?)

The only valid distinctions between this medusa and S. meleagris are in its large number of marginal lappets, and in the cleft in the middle of each octant of velar lappets. Also the 16 scapulets are hidden well up under the bell instead of extending down to about the level of the bell-margin. It may be regarded as a southern variety of S. meleagris. Haeckel describes it from 3 alcoholic specimens in the Copenhagen museum.

712 MKDUS^S OF THE WORLD.

RHIZOSTOMATA SIMPLICIA Vanhoffen, 1888.

ArMrhizids, HAF.CKEL, 1880, Syst. der Medusen, p. 565. — CLAUS, 1883, Organisation uml Entwick. Mcdusen, Leipzig. — VON

LF.NDENFELD, 1888, Zeit. fur wissen. Zool., Bd. 47, p. 210. Rhi'zostornata simphcia, VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, p. 39.

These are probably only immature or torn and regenerating forms which are rendered still more unnatural through shrinkage in alcohol. I present this account of them merely in the hope that some may be rediscovered. At present they are wholly apocryphal. A des- cription of the genera follows:

Archirhiza HAECKEL, 1880. 8 free mouth-arms, 4 separate, subgenital cavities. Haplorhiza HAECKEL, 1880. 8 free mouth-arms. A unitary, subgenital cavity. Cannorhiza HAECKEL, 1880. Mouth-arms fused along their sides, forming a mouth-cylinder.

Haeckel is the only naturalist who has seen any of these forms. They are all small and I incline to the belief that they are merely immature stages or injured and regenerating specimens of various other rhizostomae in the condition preceding the development ot the ultimate ramuli of the mouth-arms. Vanhoffen (1902, Wissen. Ergeb. Valdivia Exped., Bd. 3, Lfg. i, p. 52) believes them to be merely mutilated medusae with the branches and appen- dages of the mouth-arms lost or reduced. I have recorded them merely because they may still have a place in literature if not in the ocean.

Genus "ARCHIRHIZA" Haeckel, 1880.

Archirhiza, HAECKEL, 1880, Syst. der Medusen, p. 565. — VANHOFFEN, 1888, Bibliotheca Zoologica, Bd. i, Heft. 3, p. 39.

GENERIC CHARACTERS.

Rhizostomata simplicia with 8 simple separate, unbranched mouth-arms. With 4 separate, subgenital cavities. With 16 radial-canals, some or all of which may give rise to anastomosing side branches. The ring-canal gives off an anastomosing network of vessels which ramify through the marginal lappets. The mouths have no appendages and are found only on the ventral sides of the mouth-arms. 8 rhopalia.

Haeckel founded this genus for Archirhiza primordialis from Bass Strait, Australia. Later he describes another medusa, A. aurosa, from New Zealand, which is apparently only a later stage in the growth of his A. primorJialis. Indeed, I suspect that both of these medusae are immature, or "reconstructed" from fragmentary specimens.

Archirhiza aurosa Haeckel.

Archirhiza primordialis (young ?) , HAECKEL, 1880, Syst. der Medusen, p. 565, taf. 36, fign. I, 2. — HAMANN, 1881, Jena Zeit.

fiir Naturw., Bd. 15, p. 245 (anatomy of mouth-arms). — VANHOFFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 39. Archirhiza aurosa (mature ? ), HAECKEL, he. cit., p. 645.

Young medusa ( ?). — Bell flatly and evenly rounded, hemispherical in contraction, 2 to 3 times as wide as high when expanded. 40 mm. wide. Exumbrella finely granulated as in Aurellia. 8 rhopalia, perradial and interradial. 48 marginal lappets. In each octant 2 large median, flanked by 2 smaller velar lappets, and with 2 still smaller, rhopalar lappets flanking the sense-organs. All of the lappets are pointed. Diameter of arm-disk two-thirds as wide as bell-radius. 8 simple, separate, fleshy, unbranched, recurved mouth-arms arise in 4 pairs on either side of each perradial corner of arm-disk. These mouth-arms lack appendages, but there is a zigzag row of fringed mouths along the ventral side of each arm. These 8 lines of mouths of the mouth-arms fuse into 4 perradial lines over the mouth-arm-disk. The mouth-arms are shorter than the bell-radius and are simitar-shaped, but fleshy and blunt at their ends. 4 separate interradial genital sacs are invaginated into the stomach cavity, so the arm-disk displays 4 interradial subgenital ostia. The central stomach gives rise to 16 radial- canals, of which the 8 perradial and interradial canals give ofF branching side branches near the bell-margin. The 8 adradial canals are simple. All 16 canals and their side branches fuse with a well-developed ring-canal at the zone of the rhopalia, and on its outer side this ring- canal gives ofFa close-meshed network of small vessels which anastomose through the marginal lappets. Color ( ? ) Found in Bass Strait between Australia and Tasmania.

RHIZOSTOM.*: — ARCHIKHIZA, HAPLORHIZA, CANNOKHIZA. 713

It is highly probable that the medusa described above is only the young of the form called .-Irclurliiza attrosa, by Haeckel, from New Zealand. This is larger, being 50 mm. in diameter. There are 80 instead ot 48 marginal lappets. In each octant 8 oval, pointed velar, between 2 small, triangular, rhopalar lappets. Mouth-arm conical, more pointed than in .•/. pritnorJitilis, and 1.5 times as long as bell-radius. All 16 of the radial-canals give off anastomosing side branches.

Altogether, the differences between A. " pnmorJialis" and A. aurosa are precisely such as one would expect to occur during the growth of the medusae. They are probably only young stages of some species of Catostylus.

"Genus HAPLORHIZA" Haeckel, 1880. Haplorhiza, HAECKEI., 1880, Syst. der Medusen, p. 604. — VANHOFFEN, 1888, Bibliothcca Zoologica, Heft. 3, p. 39.

GENERIC CHARACTERS.

Similar to Archirhiza but with a unitary subgenital cavity instead of 4 cavities as in Archirhiza.

This single, subgenital cavity or "porticus" is cruciform in shape and formed by the fusion of the 4 primitive interradial genital sacs and the breaking down of the walls in the fused regions, thus forming a cross-shaped cavity beneath the stomach. It is in communication with the outer world through the 4 genital ostia, and is separated completely from the central stomach. Its side walls constitute partitions between it and the central stomach and they contain the genital products.

Haplorhiza simplex Haeckel.

Haplorhiza simfltx, HAECKEL, 1880, Syst. der Medusen, p. 604.

Bell flat, shield-shaped, 40 mm. wide, 20 mm. high. 8 rhopalia. 48 marginal lappets. In each octant 4 large, quadratic velar, between 2 tongue-shaped, projecting, ocular lappets. 8 simple, cylindrical mouth-arms, as long as bell-radius. 4 interradial, subgenital ostia, not quite as wide as the arm-disk-pillars between them. 16 radial-canals and a ring-canal. Bass Strait, southern Australia.

This medusa is very briefly described by Haeckel, but in all respects it appears to be an immature stage of some other rhizostomous medusa such as Catostylus. Its 8 simple mouth- arms lack appendages and resemble those of the immature Archirhiza primordialis Haeckel. The_jnouths are confined to-the ventral sides of the mouth-arms.

Haplorhiza punctata Haeckel.

Haplorhha [ninctata, HAECKEL, 1880, Syst. der Medusen, p. 604.

Bell flatly rounded, 40 mm. wide, 20 mm. high. 8 rhopalia. 176 marginal lappets, in each octant 10 pairs of small, rounded velar lappets between 2 small, rhopalar lappets. 8 simple, cylindrical mouth-arms, hardly half as long as bell-radius, arise in pairs from the 4 perradial angles of the wide 4-cornered arm-disk. The frilled mouths are confined to the ventral sides of the mouth-arms and there are no appendages. The 4 subgenital ostia are 3 times as wide as the columns between them.

Kxumbrella dark violet-brown, besprinkled uniformly with round white points.

Arnheims Land, coast of northern Australia. This medusa is apparently immature.

"Genus CANNORHIZA" Haeckel, 1880.

('.,1'nKjrhizd, HAKCKEL, 1880, Syst. der Medusen, p. 605. — VANHOFFEN, 1888, Bibliothcca Zoologica, Heft. 3, p. 39.

The type species is Cannorhiza connexa, Haeckel, from the neighborhood of New Zealand, South Pacific.

GENERIC CHARACTERS.

Rhizostomata simplicia with 8 simple, unbranched mouth-arms, the sides of which are fused one to another forming a hollow mouth-arm-cylinder, and leaving only the lower ends of the arms free. There were neither clubs nor filaments upon the mouth-arms. There is a unitary subgenital porticus. 8 rhopalia. The central stomach gives rise to 24 branching radial- canals which Fuse with a ring-canal. Peripherally the ring-canal gives ofFa network of vessels which ramify through the lappets.

714

MEDUSAE OF THE WOULD.

Cannorhiza connexa Haeckel.

Cannorhiza connrxa, HAECKEL, 1880, Syst. dor Medusen, p. 605, taf. 40, fign. 1-8. — VANHOFFEN, 1888, Bibliothrca Zoologica, Heft. 3, p. 39.

Bell flatly rounded, exumbrella surface finely granulated, 80 mm. wide, 30 mm. high. Gelatinous substance tough and horny in consistency. 8 rhopalia. 80 marginal lappets. In each octant are 8 small, rectangular, velar lappets between 2 small, oval, pointed, rhopalar lappets. The 8 mouth-arms are fused along their sides forming a mouth-arm-cylinder. Each mouth-arm is cylindrical, somewhat longer than the bell-radius. The short, free, lower end of each mouth-arm is simple, unbranched, curved oulward and somewhat upward. The lateral fusions of the 8 adradial mouth-arms are marked by 8 longitudinal furrows, the 4 perradial being shallower than the 4 interradial. The frilled mouths are developed only on the lower sides of the mouth-arms and there are neither filaments, clubs, nor other appendages. The 4 interradial, subgenital ostia are not quite as wide as the perradial spaces between them, and the arm-disk is not quite as wide as the bell-radius. There is a cruciform unitary sub- genital porticus and the 4 gonads are in the side walls of this space, the cruciform root being thick and gelatinous. The 4 genital membranes are much folded. The cruciform central

stomach lies above the subgenital porticus from which it is completely separated by the lateral genital membranes and gelatinous, cruciform roof of the porticus.

A wide canal extends downward from each of the 4 perradial corners of the stomach, through the columns, into the arm-disk, where they fuse at the center, forming a small cavity from which arise the 4 pairs of canals leading down the lower sidesof the 8 adradial mouth-arms. Eachmouth- arm canal gives off numerous short side branches which lead to the frilled mouths. 24 radial- canals arise from the margin of the cruciform stomach and extend outward into the subum- brella. The 8 perradial and interradial canals are about twice as wide as the others. The 4 perradial canals are very short and the 4 inter- radial very long. All 24 canals give off anas- tomosing side branches and then fuse with the ring-canal. The ring-canal, in turn, gives rise on its outer side to a fine-meshed network of narrow, anastomosing vessels which ramify through the lappets. Found near New Zealand, South Pacific. Described in detail by Haeckel.

"Stomatonema reticulatum" Fewkes. Stomalonema reticulatum, FEWKES, 1884, American Naturalist, vol. 18, p. 300.

Bell 36 mm. wide, with thick walls, thinner at margin. There are no marginal tentacles. There are 8 marginal sense-organs which bear some resemblance to those of Aurellia. Shape and number of marginal lappets ( r) The 8 mouth-arms arise from the arm-disk by 4 attach- ments and are bordered on their lower sides by a double row of mouths which also extend half-way up the upper side of each mouth-arm. 4 large, globular, ovarian sacs he in the interradii of the arm-disk alternating with the 4 primary branches of the mouth-arms. A number of radial-canals arise from the central stomach and fuse with a narrow zone of anas- tomosing vessels at the bell-margin. Fewkes does not state how many radial-canals there are in this medusa, nor does he give any account of the marginal lappets, musculature, relative sizes of the parts of the medusa, color, gonads, or mouth-arm-appendages. He mentions a single specimen found in Montevideo Harbor, Atlantic coast of South America.

The descrip;ion given by Fewkes is unfortunately too fragmentary even for generic determination, but apparently the medusa is related to Haeckel's Aurosa, but is distin- guished by having mouths on the dorsal as well as on the ventral sides of the 8 mouth-arms.

FIG. 425. — "Cannorhiza conne.va" after Haeckel, in Das Syst. der Medusen.

FOSSIL MKDUSjE. 715

FOSSIL MEDUSAE.

Fossil medusae, or in many cases fossils supposed to be those of medusae, have been described from the lower Cambrian and Devonian, and especially from the Jurassic litho- graphic slates of Bavaria wherein their preservation is so perttct that in sonic cases, as in Paraphyllitei distinctus, they can he classified accurately with relation to living forms.

Owing to the uncertainty with which we must regard many ot these fossils I have deemed it best to group them together and not to attempt the fruitless task of classify ing them, except- ing in cases wherein their state of preservation warrants such a procedure.

A thorough review accompanied by excellent illustrations ot all fossil medusae known previous to 1898 is given by Walcott in Monographs U. S. (jeological Sunev, vol. 30, 1898, and this work should be consulted by all students of the subject, for the account here gisi-n does not attempt to present detailed descriptions.

Medusina radiata Walcott.

Aitylospongia radiata, LlNNARSSOH, 1871, Kongl. svensk. Vet.-akad. H.mdl., vol. »}, No. 7, p. 15, plate ;. figs. 15, 16.

MeJusites radiums, NATIIORST, iXSi, Kongl. svcnsk. Vet.-akad. Handl., vol. HI. No. r. i ;-. pl.iii- d. figs, i, 2. — (?)Po\ir>. M.

1896, Jahrbuch, K.-k. geol. Itt-iclisanstalt, Bd. 45, p. 501, taf. 14, fig. 3. Medusina radiata, WAI.COTT, 1898, Monographs U. S. Geol. Sun"., vol. 30, p. 56, plate 28, fig. 2.

This fossil medusa from the lower Cambrian sandstone of Sweden is probahh mie ot the ./Equoridae and bears a general resemblance to the genus lygodactyla. Hell 40 to 60 mm. wide. Central stomach 25 to jo mm. wide. 130 to 150 radial-canals which occasionally branch. Subumbrella with radiating stnng-ot-pearl-hke papillae as in lygodactyla. Nathorst describes these papilla? as being upon the radial-canals, but to me it seems more probable that thev are interradial as in Zygodactyla.

Pompeckj's somewhat similar medusa trom the middle Cambrian beds ot Bohemia is probably an jEquorea, anJ not a ZygoJactyla.

Medusina princeps Torell.

Protohellia princeps, TORF.LL, 1870, Lunds Universitets Arks-Skrift, 1869, No. 8, p. 10.

Aa\losponiga radiata, LI.NS*RSSO\ (in part), 1871, Kongl. svensk. Vct.-akad., Hand]., lid. i), \r. 7, p. 13, taf. 2, fig. 15.

Medusita jtrcoun, NATHORST, 1881, Kongl. svensk. Vet.-akad. Handl., Bd. 19, Nr. i, p. 25, taf. 25, taf. 5, fign. 5, 6 ( ?).

Mrjufitts princeps, \\\\ now, 1890, Trans. Royal Soc. Canada, vol. 8, p. 140.

Medusina princeps, WALCOTT, 1898, Monographs U. S. Gcol. Surv., vol. 30, p. 54, plate 28, fig. I.

This fossil from the lower Cambrian of Sweden is of doubtful affinities. Nathorst's conclusion that it is one of the Cyaneidas because the exumbrella floor of the stomach exhibits polygonal facets appears to me to be too venturesome, for the radiating furrows of the sub- umbrella resemble the radial-canals of /Equorea.

Medusina deperdita Walcott.

Acatepha deperdita, BEYRK-II, 1X41), X.eitschrift dcutsch. Gcol. Gcscll., Bd. I, p. 437, taf. 39, fig. i. Medusiies deperdiius, HAECKF.L, 1865, Zcitschrift fiir wissen. Zool., Bd. 15, p. 506, taf. 39, fig. i. Medusina deperiiii, \\.\u 01 r, i i . '.1 r.iph U. S. Geol. Surv., vol. 30, p. 91, plate 44, fig. I.

It is possible that this fossil medusa from the Jurassic limestone of Eichstiidt may belong to the genus Cunoctantha, but there are no tentacles and we have only the S stomach-pouches upon which to hazard this inference The bell is 70 mm. and the diameter through the stomach- pouches 45 mm. wide.

Paraphyllites distinctus Maas. Paraphyllites distinclus, MAAS, 1906, Neu. Jalirh. Min. Gcol., Palaontol., Bd. 2, p. 90, 4 fign.

The preservation of this fossil from the Jurassic lithographic slates is so perfect that its affinities with living medusz can be determined. It is therefore described on page 541) in connection with Paraphyllina to which it is closely related.

716 MEDUSA OF THE WORLD.

Cannostomites multicirrata Maas. Cannostomites muliicirrata, MAAS, 1902, Palaontographica, vol. 48, p. 303, taf. 23, fig. i, text-fig.

This is a fossil from the Jurassic lithographic slates of Bavaria. A single specimen was studied by Maas. It may possibly be allied to Atolla. Only the subumbrella is known. Bell about 100 mm. wide. An open, central mouth with 4 perradial, gelatinous columns. Sub- umbrella simple with 4 interradial sickle-shaped, notched, and swollen gonads. Marginal ring-muscle entire and powerfully developed as in Atolla. Numerous marginal lappets of varying sizes arranged in multiples of 4. Short, simple tapering tentacles arise from notches between the lappets.

Atollites minor and Atollites zitteli Maas. Atollitti minor and A. ziltili, MAAS, 1902, Palaontographica, Bd. 48, p. 319, taf. 23, fign. 5 und 6.

These fossils are from the lower chalk of Carpathia from the Warnsdort strata. There are more than 10 marginal lappets in high relief, quite variable in size and number. A small, plain center of the exumbrella and an intermediate zone with raised streaks radiating out- wardly. The medusas may be allied to Atolla. They are well figured by Maas.

Acraspedites antiquus Haeckel.

Mfdusiles antiquus, HAECKEL, 1865, Zeit. fur wissen. Zool., Bd. 15, p. 509, taf. 39, fig. 2.

Acraspedites antiquus, HAECKEL, 1869, Zeit. fur wissen. Zool., Bd. 19, p. 559; 1880, Syst.der Mcdusen, p. 647. — VON AMMON, 1886,

Abhandl. Math.-phys. Classe Konigl. bayer. Akad. Wissen., Bd. 15, p. 157. — WALCOTT, 1898, Monographs U.S. Geol.

Surv., vol. 30, p. 75, plate 44, fig. z.

This is the vague impression of a medusa in the Jurassic white coral limestone, litho- graphic slate of Eichstadt, Bavaria. It is about 140 mm. in diameter and appears to have 8 marginal lobes. The sculpturing of the bell may place it among the Coronatae, but Haeckel is inclined to classify it with the Pelagidae.

Semaeostomites zitteli Haeckel.

Semaeostomites zitteli , HAECKEL, 1874, Jena. Zeitsch. fur Naturw., Bd. 8, p. 323, taf. n; 1880, Syst. der Medusen, p. 647. — VON AMMON, 1886, Abhandlung Math.-phys. Classe Konigl. bayerischen Akad. Wissen., Bd. 15, p. 157. — WALCOTT, 1898, Monographs U. S. Geol. Surv., vol. 30, p. 70, pi. 39, text-fig. 17.

This semaeostomous medusa is found fossil in the Jurassic lithographic slate of Solenhofen, Bavaria. According to Haeckel the disk is 80 mm. wide, mouth with 4 lips each about 80 mm. long and 10 mm. wide. Central stomach cruciform. 4 interradial, elliptical, genital pouches each 8 to 10 mm. wide. 16 unbranched ( ? ) radial-canals, 4 perradial, 4 interradial, and 8 adradial. A ring-canal at some distance inward from the margin. 120 to 128 marginal lappets, and an equal number of tentacles each about 30 mm. long. This medusa is apparently one of the Ulmaridae allied to Discomedusa.

Eulithota fasciculata Haeckel.

Eulithola jasciculata, HAECKEL, 1869, Zeit. fur wissen. Zool., Bd. 19, p. 549, taf. 42, fign. 1,2; 1880, Syst. der Medusen, p. 647.— VON AMMON, 1886, Abhandl. Math.-phys. Classe Konigl. bayer. Akad. Wissen., Bd. 15, p. 157. — WALCOTT, 1898, Mono- graphs U. S. Geol. Surv., vol. 30, p. 73, plate 45, figs. 3, 4.

This is a fossil medusa from the Jurassic lithographic slate of Solenhofen, Bavaria.

16 marginal lappets. 8 clusters, each composed of at least 4 tentacles, which arise from 8 perradial and interradial ( ? ) thickened pads between the lappets. These pads may represent the 8 rhopalia. 16 crescentic gonads around the stomach-margin. 16 interlobular radial- canals. 4 (?) simple, short lips. The affinities of this medusa are uncertain but its nearest living ally appears to be Sthenonia or Poralia.

Myogramma speciosum Maas.

Myogramma speciosum, MAAS, 1902, Palaontographica, Bd. 48, p. 298, tafn. 22, 23. — VON AMMON, 1908, Geonostischen Jahres- heften, Jahrg. 19, p. 174, fign. 2, 3.

This fossil is from the lithographic slate of Solenhofen. Discomedusas with flatly rounded bell. 4-rayed in the organization of the central stomach. 8-rayed at the bell-margin. In the

FOSSIL MEDUSA. 717

subumbrella a wide marginal ring-muscle, an intermediate zone of 16 feathered arcades as in Cassiopea, and an inner zone of ring-muscles around the central stomach.

At the bell-margin there appear to be numerous thickly set, short, branched, tree-like tentacles. The mouth-parts are lost. Maas studied 3 imperfect specimens of this remarkable medusa which appears to be distinguished from_ali other Scyphomedusx by its branched marginal tentacles. His best preserved specimen was 300 mm. wide.

Genus MEDUSINA Walcott, 1898.

Medusina, \\AI.COTT, 1898, Monograph U. S. Gcol. Surv., vol. 30, p. 49.

Walcott proposes the name Medusina to designate all fossil medusa whose generic char- acters can not be determined.

Among the most obscure are AI. quadrata, M. Liuncta, M . staurophora, .M . circularis, and M. porpitina from the Jurassic lithographic limestone of Ba\;ma, and M. utirai Horn the Permian. All of these are well described by Walcott, loc. cit., pp. 93 to 96. Beyond the fact that these fossils are apparently medusa; not much can be said of them, and in most cases we can not be certain as to whether they are Scyphomedusx or Hydromedusx.

Medusina costata Walcott.

o

Spatan^opsis costata, TORRELL, 1870, Lunds I'niversitets Ars-Skrift, 1869, No. 8, p. 11.

Af>elacrinuslindstromi,LitiHARsso*i, 1871, Kbngl. svcnsk. Vct.-akad.Handl.,Bd.9, Nr-7, p. n.taf. i,fign.6--,taf.2, fign. 10-14. Medusitel lind-trami, SCHMIDT, 1888, MOin. AtaJ. Iinp.Sci.St.Petersbourg, scr. 7, tome 36, p. 27, planchc 2, figs. 34, 35.— WAL- COTT, 1891, Tenth Ann. Report, U. S. Gcol. Surv., Part I, plate 56, figs. i-ic. Medusites costatas, MATTHEW, 1890, Trans. Royal Soc. Canada, vol. 8, p. 141. Medusina costala, \\ALtorr, iSyS, Monographs, U. S. Geol. Surv., vol. 30, p. 49, plates 29, 30.

This fossil from the lower Cambrian sandstone of Sweden, at Lugnas and Timmerdala in Mount Billingen, is probably an Aurellia. The best description is presented by Walcott.

Medusina geryonides Huene.

Medusina grryonides, HUENE, 1901, Neucs Jahrbuch fur Mineralogie Geol. und Palaeontol., Bd. I, p. I, taf. l.fign. 1,2. — Fl'CHS, 1901, Centralblatt fiir Mineral. Geol. und Palaeontol., Jahrg. 1901, p. 166.

This fossil medusa is from the Murchison sandstone of Wiesensteig in Wiirtemburg. It is about 28 to 30 mm. in diameter. In the center there is a crater-like elevation with an irreg- ular, flat, 6-sided knob at its middle. Surrounding this crater-shaped center there is a zone of 12 radiating concavities, the deepest being 2.5 mm. deep. Huene suggests that this medusa may have been related to the Geryomdx, but this is wholly problematical, and it appears to me that it might equally well be a cast of Brooksella. Fuchs casts doubt upon its being a fossil medusa.

Laotira cambria Walcott.

Laolira cambria, WALCOTT, 1896, Proc. U. S. Nat. Mus., vol. 18, p. 613, plate 32, figs. 1-8; 1898, Monographs U. S. Gcol. Surv., vol. 30, p. 32, plates 5-19, 21-23.

This is a fossil from the middle Cambrian shale of Coosa Valley, Alabama, and is supposed to be that of a medusa. It is a remarkably variable form and quite distinct from any living medusa. It probably reproduced by fission as does Gastroblasta.

Walcott defines it as Discomedusae with a lobate umbrella with 4 to 12 lobes in simple forms and with a large number in the compound forms. No tentacles and no central mouth- openings in the adult. A simple radial-canal in each lobe of the umbrella and in the inter- radii. Oral arms represented by interradial lobes attached to the central axis and to the central lobes. Described in full detail by Walcott, 1898. It shows a tendency to intergrade in its simplest forms with Brooksella confusa from the same formation.

Dactyloidites asteroides Walcott.

Butlwtrephis (?) asteroides, FITCH, 1850, Trans. New York State Agricult. Soc., vol. 9, p. 863.

l)ait\loitliut bulbosiis, HALL, 1886, 391!! Ann. Report State Museum Nat. Hist. New York, p. 160, plate 11, figs. I, 2. Dactyloidites asteroides, \\'ALCOTT, 1891, loth Ann. Report U. S. Geol. Surv., Part I, p. 605, plates 57, 58, fig. in; iS<iS, Mono- graphs U. S. Gcol. Surv., vol. 30, p. 41, plates 24-28.

This fossil is from the lower Cambrian terrane of Eastern New York at Pemhvn Ouarry, Middle Branville, Washington County, and from St. Albans, Vermont. It is an irregular,

718 MEDUSAE OF THE WORLD.

star-like fossil, and sometimes two stars are joined by a single lobe. It appears to have been gregarious, for Walcott records 42 specimens on a slab of slate 37 by 62 inches. There is of course no proof that these fossils are those of medusae.

Rhizostomites admirandus Haeckel.

Rhizostomites admirandtts, HAECKEL, 1866, Neues Jahrbuch fiir Min. Geol. und Paleontol., p. 261, taf. 5; 1869, Zeit. fur wissen. Zool., Bd. 19, p. 557; 1880, Syst. der Medusen, p. 647. — BRANDT, 1871, Mem. Acad. Imp. Sci., St. Petersbourg, ser.y, tome 16, p. I, planche I, figs. 1-4. — VON AMMON, 1886, Abhandl. Math.-phys. Classe, Akad. Wissen Miinchen, Bd. 15, p. 123, 158, 163, taf. 2, fig. 2. — WALCOTT, 1898, Monographs U. S. Geol. Surv., vol. 30, p. 76, plates 40,42. — MAAS, 1902, Palaeontographica, Bd. 48, p. 306, taf. 23, fig. 2. — VON AMMON, 1908, Geonostischen Jahresheftcn, Jahrg. 19, p. 174, fig. i .

von Ammon, who has made the most thorough study of this fossil from the Jurassic lithographic limestone ol Solenhofen and ot Eichstadt, Bavaria, has decided that it is identical with Haeckel's Rhizostomites lithographicus, and that Leptobrac lutes trigonobrachius is probably the same medusa turned over on its side. He also concludes that Haeckel's Hexa- rhizites insignis is only a 6-rayed aberration of the same medusa. A thorough review of ihe literature of this subject and excellent figures are presented by Walcott, 1898, loc. cit.

According to von Ammon and Walcott the disk in Rhizostomites is round and as large as 400 mm. in diameter, with 4 to 8 principal lobes and about 128 small marginal lappets of various sizes, and indentations of the bell-rim marking the places of the 8 marginal sense- organs. No marginal tentacles. A wide zone of circular muscles in the subumbrella, unbroken in the rhopalar radii. 16 radial-canals, 8 rhopalar and 8 inter-rhopalar; and a circular canal in the external third of the umbrella. A strongly marked, circular depression between the muscle- zone and the arm-disk may indicate an inner ring-canal. 4 not very wide subgenital ostia, with 4 opercula forming lappets. Probably 8 long, thin mouth-arms with crinkled appen- dages, and apparently with a tassel-shaped tuft at the lower end.

This is undoubtedly a Rhizostomous medusa which appears to belong to an extinct genus related to the modern Rhizostomata triptera or lonfera. Maas, 1902, gives a remarkably clear photograph of the margin showing one of the sense-organs, and he discusses the probable form of the gonads.

Brooksella alternata Walcott.

Brooksella alternata, WALCOTT, 1986, Proc. U. S. Nat. Mus., vol. 18, p. 612, plate 31, figs. 1-5; 1898, Monographs V. S. Geol. Surv., p. 23, plates 1-4.

This fossil from the middle Cambrian shale from Coosa Valley, Alabama, is supposed to be that of a medusa. They are 40 to 50 mm. in diameter. From 5 to 20, usually 5 to 8, more or less distinct marginal lobes. No tentacles. A simple radial-canal in each lobe of the umbrella. Oral plate quadripartite with 4 oral arms arising from it. Central stomach well developed, but apparently there was no central mouth-opening.

This form was possibly allied to the Rhizostomae and may have had habits similar to those of Cassiopea.

Brooksella confusa Walcott.

Brooksella confusa, WALCOTT, 1896, Proc. U. S. Nat. Mus., vol. 18, p. 612, plate 31, figs. 7a-b; 1898, Monographs U. S. Geol. Surv., vol. 30, p. 30, plate 3.

In Brooksella confusa the marginal lobes do not unite at the center of the bell but join irregularly, whereas in B. alternata they radiate from the center of the disk. This fossil is found in the middle Cambrian shale of Coosa Valley, Alabama.

Brooksella rhenana Kinkelin. KINKELIN, 1903, Bericht Senckenberg Naturf. Gesell., Theil 2, p. 89, taf. I, fign. I, 2.

An 8-lobed medusa from the middle Devonian of Ruplach. Only one specimen, showing its exumbrella, was found, and this appears to me to be identical with, or at any rate very closely related to, Walcott's Brooksella alternata.

APPENDIX.

PREOCCUPIED GENERIC NAMES.

The establishment of the International Commission upon Zoological Nomenclature and the general recognition which the code that controls its decisions has won tor itself among naturalists makes it more than ever desirable that the validity of the generic names we now use should be firmly established. Accordingly, the tenability of each and every generic name adopted in this work has been made the subject of a thorough search, and I am somewhat surprised to find that certain names which have been used for generations without question ot their priority are actually preoccupied for other groups of animals and can not lit- applii-d to medusae. Unfortunately I did not carry out this investigation until after volumes I and II were printed. A list of the generic names which can not be applied in medusae follows:

Corynitis (page 71, Vol. I)=Linvillea nom. nov.

Both Corynitis and Corynctcs are preoccupied, the former having been applied to Arach- nids in 1854, and the latter to Coleoptera by Herbst, 1792. Wagner's Plotofnnlc is vaguely described and figured, but it appears to me to be a Protiara, and Browne's TiarifoJon, while it may be a "Corynitis," is too imperfectly known to be determined. We must therefore gi\e to this genus a new name, and I propose Linvilh-a in honor of Dr. Henry R. Liiiulle, win; found the hydroid. The type species is therefore Linvillca agassizii.

Slabberia (page 73, Vol. I)=Dipurena.

Slabberia is preoccupied by Oken, 1815 (Lehrbuch der Naturgesch.,Theil 3,Zool., p. 828 ), for Slabber's Medusa marina, which is an Obelta and therefore wholly different from the medusa to which the name Slabberia was applied by Forbes, 1846. We must therefore drop Slabberia in the sense in which I have used it and substitute for it the generic name I)ipur,->xi McCrady, 1857.

Turris and Tiara = Clavula.

Both Turris and Tiara are preoccupied and can not be used for medusae. The name Clavula may be applied to these medusae, as has been explained on page 491. Volume II.

Laodicea (see page 201, Vol. I).

According to L. Agassiz, 1842-46, Nomenclator Zoologicus, the generic name I.aoJic,-<i was used by Lamouroux, 1816, Hist. Polvpiers Coralligenes, and this statement of Agassiz's is copied in Scudder's Universal Index to Genera in Zoology, 1882, p. 167. Upon refer ring to Lamoroux's work, however, I can not discover that he used the name LaoJitsii. and lulu \c that Agassiz is mistaken, and that Laodicea of Lesson, 1843, mav be retained for medusa?. Laodice is preoccupied, having been used by Gemminger, 1871, for Coleoptera, before Haeckel, 1879, applied it to medusae, but this does not interfere with the use of LaoJiiai. Indeed, several medusa genera escape by so narrow a margin; for example, Amaltheii takes precedence over Amalthaea, yet the latter, differing as it does by a single letter, may be used. Similarly Chrysaor takes precedence over Chrysaora, yet both may be used.

719

720 MEDUSAE OF THE WORLD.

HYDROMEDUS^E.

Maas, 1909 (Abhandl. Math. phys. Klasse der K. Ba)-er. Akad. der Wissenschaft, Miin- chen, Suppl. Bd. I, Abhandl. 8), gives a description of 23 hydromedusae from Japan obtained upon Doflein's voyage.

The old species are Cytais vulgaris, Tiara papua, Proboscidactyla flavicirrata var. stolon i- fera, Spirocodon saltatnx, Ettcheilota paradoxica, Phialidium pacificism, Phialidium discoida, Mesonema pensile, Gomonemus vertens var. depressum, Ohndioides formosa, Liriope rosacea, Rhopalonema velatum, Aglaura hemistoma, jfLgina rosea, Solmundella bitentaculata, Cunina peregrina, and Salmans rhodoloma.

The new forms are called Sarsia japonica, Nemopsis dofleini, Turritopsis nutricula var. pacifica, and Willsia pac:fica. A Zanclea and an Obelia are possibly new.

It is interesting that Eucheilota paradoxica, known hitherto only from the Florida-Bahama region, should be reported from Japan.

One of the most valuable features of Maas's paper is his redescription, accompanied by an excellent account of the post-embryonic development of Spirocodon saltatri\. Reviews of his account of this, and of the new forms, are presented in this Appendix.

An important paper upon Arctic Hydromedusae and Scyphomedusae is that of Hartlaub, 1909, Croisiere Oceanographique Belgic a dans la Mer du Gronland, Meduses, 18 pp., planches 76-77. Unfortunately this has reached me too late to be reviewed for this work.

Pennaria tiarella (see page 25, Vol. I). Pennaria tiarella, HARGITT, G. T., 1909, Bull. Mus. Comp. Zool. at Harvard College, vol. 53, p. 164, 5 plates, 44 figs.

Hargitt studies the development of Pennaria tiarella and finds that the obcyte nucleus dissolves within the germinative vesicle before the nuclear membrane is ruptured. The linine network of the germinative vesicle extends to the nucleolus, so that an interchange of substances may possibly occur between the chromatin and the nucleolus.

The two polar bodies appear to be formed at about the time of the liberation of the medusa, by a process of mitosis of which Hargitt gives a detailed account.

Fertilization usually occurs after the polar bodies have been formed. The cytoplasm is very active at this time, forming protuberances upon the surface of the egg. The male and female pronuclei unite by apposition.

The first cleavage spindle seems to form from the cytoplasm. The cytoplasmic division is delayed, the second nuclear division being completed before the first cleavage furrow has cut half through the egg.

Hargitt disagrees with Beckwith, 1909, and finds that the polar bodies are seen only at or near the time of the liberation of the medusae, about 7 p. m. He also finds, contrary to Beck- with, that the nucleolus disappears within the germinative vesicle before the dissolution of the nuclear membrane, whereas Beckwith states that it is cast out into the cytoplasm.

Corymorpha nutans (see page 31, Vol. I). Cor\morpha nutans, MALARD, 1907, Bull. Museum Paris, p. 563. — TORREY, 1907, Science, vol. 25, p. 734.

Malard finds Corymorpha nutans when dredging in deep water northeast of the He Tati- hou, coast of France, and Torrey observes spontaneous fission in the stems of the hydroid.

Sarsia rosaria (see page 59, Vol. I). Sarsia rosaria, KISHINOUYE, 1910, Journ. College of Sci., Tokyo, vol. 27, art. <j, p. 24.

Kishmouye finds this medusa off the Kurile Islands, north of Japan. A. Agassiz records it from the Pacific coast of North America.

Sarsia japonica Maas. Sarsia japonica, MAAS, 1909, Abhandl. Akad. Wissen., Munchen, Suppl. Bd. I, Abhandl. 8, p. 6, taf. i, fig. i.

Bell 12 to 15 mm. high, 4 to 6 mm. wide, with flatly rounded apex. Bell walls 2 mm. thick. Manubnum nearly cylindrical, four-filths to five-sixths as long as the depth of the bell- cavity. Gonads scattered irregularly over the manubnum from the base to near the mouth.

APPENDIX.

721

Tentacle-bulbs large pyramidal, without ocelli and without nettling warts. Tentacles tapering, shorter than bell-height when contracted, their proximal pans with scattered nematocysts, and distal two-thirds with ring-like nettle-batteries. 4 straight, slender radial-canals without an axial-canal above the stomach. (Jonads and tentacle bulbs yellowish-brown, other pans colorless. From Todohokke and Hokkaido, Japan. Hvdroid unknown. It is probably an Arctic form.

It is distinguished from S. resplendent and S. brachygaster by having no ocelli, and from .V. itpiiula bv having no axial-canal and by its bluntly rounded apex. Its nearest relative is •V. flammed, with which, indeed, it may prove to be identical.

Fi<;. 426. — Coryrnorpha pendula. After L. Agassiz in Contributions to the Natural History of the United States, vol. 4.

Eleutheria (see page 93, Vol. I).

Eleutheria, BADT, 1907, Das Seewasser-Aquarium, Mapdclmrg, 2 fign. — KRUMBACH, 1907, Britrage 7.ur Kcnntniss der Medusa Eleutheria, Brcslau, 47 pp.

Krumbach gives a detailed account of Eleutheria. Unfortunately I have not seen his paper and am unable to review it.

Cladonema radiatum (see page 99, Vol. I).

Cltitlonema riitjialurn, BINDF.R, 1908, Bull. Must:um, Paris, p. ^85. RH'HTKRS, 1908, /ool. An^eijjrr, Bti. 3;, p. 687.

Binder gives a good description of the hydroid from the Atlantic coast of France, and Richters records it from Helgoland, German Ocean.

722 MEDUSAE OF THE WORLD.

Urashimea globosa Kishinouye.

Urashimea globosa, KISHINOUYE, 1910, Journal College of Sci., Tokyo, vol. 27, art. 9, p. 27, plate 5, figs. 27-29. Young medusa, Urashimea macrotentaculata, Ibid-, p. 28, fig. 30.

Bell 17 mm. high, 15 mm. wide, globular with very thick walls. Numerous meridional bands of nematocysts arranged more or less definitely in 4 perradial groups. There are 4 interradial, hollow spaces between the exumbrella and the subumbrella, and these have many pointed processes on the aboral side. Unfortunately Kishinouye's description is lacking in detail and his figures only add to my confusion respecting the nature of these spaces. Are they entirely cut off" from the gastrovascular system ? "The radial-canals have many minute processes on the aboral side."

There are 4 tapering tentacles longer than bell-height and with numerous, short, capped filaments on all sides. Each tentacle with an abaxial ocellus at its base. Mouth with 4 tri- angular lips. The gonads are 4 pouches hanging down from the horizontal parts of the radial- canals near the stomach. Each gland is broadest at its "axial extremity" and exhibits two longitudinal folds. Found at Saghalm and at Monbetsu in Kitami, Hokkaido.

This remarkable medusa is so briefly described and figured that I can not venture to define its generic characters. Kishinouye states that it is one of the Cladonemidae. From Japan and Saghalin Island.

Urashimea macrotentaculata is apparently a young specimen of the same medusa from Kuno in Suruga Bay, japan.

Turritopsis pacifica Maas.

Turritopsis nutricola var. pacifica, MAAS, 1909, Abhandl. Akad. Wissen, Miinchen, Suppl. Bd. i, Abhandl. 8, p. 14, taf. i, fign. 6-8; taf. 2, fig. 9.

Bell of adult medusa 8 to 9 mm. high, 5 to 6 mm. wide. This form is distinguished by the number and arrangement of its tentacles, 120 to 150 of which arise, not in a single row, as in the Atlantic Turritopsis, but in 3 or even 4 rows, one above the other; the number of rows increases wr. h age. The tentacles are tapering, their entoderm chordate, and each has a small, projecting ocellus on the abaxial side of its swollen bulb, whereas the ocelli of the Atlantic Turritopsis nntriciila are on the axial (inner) sides of the tentacles. There are 4 diffuse interradial gonads. The manubrium and radial-canals are as in T. nittritnla. Gonads and stomach orange, ocelli red, entoderm of tentacles greenish. Ten specimens, from Sagami Bay near Misaki, |apan, in Ociober.

This form differs so markedly from the American medusa that we may safely call it a distinct species.

Rathkea octopunctata (see pages 175, 177, Vol. I). Cytifis octopunctata, MARKOW, 1908, Zool. Anzeiger, Bd. 33, p. 664.

Markow finds that this medusa is very abundant near Sebastopol between February and April, from the surface to a depth of not more than J feet. Budding medusae were abundant from January 27 to February 12 in water of 6.1° to 6.9° C. The rediscovery of this medusa in such abundance in the Black Sea makes it practically certain that it was described by Brandt, 1838, under the name Rathkea blumenbachii, and that this name is merely a synonym of Rathkea octopunctata, which is the type of the genus. Brandt's figure shows pinnately- branched oral tentacles, but this is evidently a mistake.

Rathkea octopunctata var. grata (see page 179, Vol. I). Lizzia shimiko, KISHINOUYE, 1910, Journal College of Sci., Tokyo, vol. 27, art. 9, p. 25, plate 5, fig. 24.

I believe this to be identical with the Arctic variety of R. octopunctata, commonly called R. grata. Kishinouye found it to be quite common in winter at Misaki, Hamana Inlet, and in Omura Bay, Japan. He says that the bell is 2 mm. wide and that the 8 basal bulbs are red and each gives rise to 3 or 4 tentacles. The manubrium and medusa-buds are pinkish. Kishinouye's description and figure might equally well have been derived from a study of R. octopunctata var. grata, from our Massachusetts coast, the Japanese and American medusae apparently being identical in all respects.

The medusa is so abundant in Japan that it has received the vulgar name "shimiko."

APPENDIX.

Nemopsis dofleini Maas.

\riiitif>sis Jofteini, MAAS, 1909, AWiandl. Akad. \Vis-en., Munchen, Suppl. Bd. i, Abhandl. 8, p. 1 1, taf. i, fign. 4 und 5. Favonia nippoaica, KISHINOI vt, 1910, Journal College of Sci., Tokyo, vol. 27, art. 9. p. 26, plait 5, fig. 25. (?) FiK-ytiii iulxttii, Ki-iiiN'ii \>, Mil/., p. 26, platt 5, fig. 26 (contracted specimen from Korsakoff).

Ir is probable that \,-ni(j/)sis ilnfirini Maas is identical with l-',n-nni<i ntpponica Kishinouye and that the pair of small median tentacles of each perradial cluster was lost in the 9 preserved specimens studied In Maas*- These are very brittle and are often lost in large specimens of the American Nemopsis, edffecially after preservation in formalin. Kishinouye rinds that the marginal tentacles arise in t\vo rows from the "epaulets," whereas Maas finds them in a single, closely crowded row. The appearance of two rows is often due to contraction or to crowd- ing. Bearing these differences in mind, I present the descriptions of both authors in order that they may be compared in detail.

Size in mm. Shape of brll.

Shape of tentacular ep.iulet from which each IM

ni.irejn.il trnt.i' !r .IMM-S.

Number of tentacle;- in each perradial marginal <:lu ter.

Number of dichotomous branchings of the oral tenta- cles.

Size and shape of gonads.

Color.

Where found.

Nemopsis dofleini.

20 to 22 high, 12 to 15 wide.

4- ided. prismatic with flatly rounded apex and thick walls.

Cleft in the middle. The two halves wing- shaped.

40 to 60, simple, tapering, set in one row. 'I rn- i.ules shorter than bell-height. No median < LavatC pair of tentacles observed. Ocelli at the lent.ule bases.

5 t° 7-

In the form of a double fold along the radial- canals almost reaching the ring-canal. A per- radial separation between each half of each gonad.

Stomach, gonads, and tentacle-bulbs yellowish, ocelli dark brown.

Bay of Tokyo, Japan.

Nemopsis "nipponica."

17 high, 15 wide. As in N. dofletni.

As in N. dofleini.

About 50 in two rou s. A median pair of small il.iv.it,- tent.u-les. ( Helli at tentacle bases.

About 10 tunes.

As in N. dofleini but shorter, being, however, more than half as long as radial-canals.

Tentacle-bulbs and lips orange, ocelli brown. Male- gonads bluish, female pale yellowish.

Bays of Tokyo and Mikawa, very abundant in spring.

Willsia pacifica Maas.

ll'illia paeifca, MAAS 1909, Abhandl. Akad. \Vissen., Munchen, Suppl. Bd. i, Abhandl. 8, p. 17, taf. 3, fig. 16.

Bell flat, 2 to •{ mm. high, 5 to " mm. wide; 6 regularly spaced radial-canals arise from the stomach and branch so that about 6X18 terminal canals reach the bell-margin. Manu- brium flat, 6-sided, with <i complexly-folded lips. 96 to 108 tentacles as numerous as the terminal branches of the radial-canals. 96 to 108 short, narrow nettling streaks upon the exumhrella, alternating with the tentacles. No ocelli. Ring-canal rudimentary. Color (?) Coast of Japan in September. One specimen.

Polyorchis karafutoensis Kishinouye. Polvorchis kara/ulornsis, KISHINOUYF:, 1910, Journal College of Sci., t"niier-it\ T»!.vo. vol. 27, art. 9, p. 30, plate 5, fig. 31.

This medusa differs fmm /Vy/'v/n-f pcniciHuta in its greater size, being 60 mm. high and

50 mm. wide. Also iis gonads are dichotomously branched, main of the marginal tentacles are forked, and the nn»-canal gives orr centripetal branches.

There are about 40 gonads, 10 on each radial-canal, and these are longer than the manu- brium, which latter is of the size and shape seen in P. penicillata. There are about 120 marginal

724

MEDUSA OF THE WORLD.

tentacles, said to arise in several rows from the bell-margin. Each of the 4 radial-canals gives oft from 14 to 16 long, lateral branches which branch at their outer ends but do not anastomose. Many short, usually unbranched, centripetal canals arise from the ring-canal and end blindly.

A single specimen was obtained at Korsakoff, Saghalin Island, on September 19, 1906.

In the character of its canal-system this medusa is intermediate between Polyofchis and Spirocodon, but the bell-margin is simple, not cleft into lappets, and the tentacles are spaced at equal distances apart around the margin.

Spirocodon saltatrix Tilesius (see page 220, Vol. I). SpirocoJon saltatrix, MAAS, 1909, Abhandl. Akad. Wissen., Munchen, Suppl. Bd. I, Abliandl. 8, p. 18, taf. z, fign. 10-13.

Maas gives by far the best published description of this medusa and corrects several errors of former students, especially in respect to the character of the gonads.

When the bell is only 12 mm. high and 5 mm. wide, with high, slightly bulging sides and dome-like apex, the gelatinous substance is thick, being thicker in the perradii than in the 8 adradii. The circular muscles of the subumbrella are entire. There are 8 clusters, each with about 20 tapering tentacles. The stomach is a long, simple tube with 4 distinct lips

FIG. 427. — Spirocodon saitniri.v. After Maas in Abhandl. Akad Wissen., Munchen. A, young medusa with small gonads and tentacles, still in 8 clusters. B, half- grown medusa, showing one of the gonads. C, full-grown medusa, tentacles and canals omitted to show the form of one of the^gonads.

APPENDIX. 725

which are at a level about one-eighth of the height of the bell-cavity above the margin of the bell. There is a well-developed peduncle above the stomach. The 4 radial-canals each give off about 20 branched but non-anastomosing side branches in the subumbrella. Over the peduncle ihe canals do not branch. There is a ring-canal with 4 short inn. i radial, branched, blindly ending centripetal canals. In this voung stage the gonads are not apparent.

The gonads begin to develop along the 4 radial-canals on the peduncle close to the base of the stomach when the medusa is about 18 mm. high and 15 mm. wide (see text-figure 426A). The radial-canals at this point begin to elongate more rapidly than the portion of the peduncle upon which they lie, and thus they begin to loop outward into the subumbrella cavity. Finally these freely-projecting canals twist spirally and hang downward into the bell- cavity, the canal extending around the free edge of a mesentery (figs. 42615 and c). In later stages the bell-margin develops 8 indentations, 4 perradial and 4 interradial, with 8 adradial convexities between. The 8 clusters of tentacles of the young medusa spread laterally as m \\ tentacles develop, until finally the tentacles become congruous entirely around the bell-margin.

The specimens studied by Maas were from the shore at Yokohama and from the R:us of Tokyo and Sagami, Japan. The largest were 40 mm. high and 30 mm. wide.

According to Maas the 4 interradial vessels are the only blindly ending canals which arise from the ring-canal, this being contrary to the observations ot other authors.

Obelia congdoni Hargitt (see page 248, Vol. II).

Otelia hyalina, CONGDON, 1907, Proc. American Acad. Arts and Sci., Boston, vol. 42, p. 468, figs. 7-9. Obelia congdoni, HARC.ITT, C. W., 1909, Biol. Bulletin, Woods Hole, vol. 17, p. 375.

Hargitt believes this to be specifically distinct from 0. hyalina Clarke. The branches of the stem do not arise in the axils of the hydrothecx as in O. hyalina. The gonangia are larger, being about 4 times the length of the hydrothecae, and the opening is not simple, but there is a neck with everted rim. Moreover, the colony is 20 to 30 mm. high and profusely branched instead of being about 12 mm. high and but little branched. The newly liberated medusa has 24 tentacles, but within 10 or 12 hours it has 30 to 36. The hydroid is found upon drifting Sargassum and is a tropical form.

Staurophora mertensii (see page 291, Vol. II). Slaurofihora discoidea, KlSHlNOUvr,, 1910, Journal College of Sci., Univ. of Tokyo, vol. 27, art. 9, p. 29.

Kishinouye describes this medusa from Japan and Saghalin Island. I believe it to be identical with S. tncrtcnsii. He states that it closely resembles 5. mertensii, but that there are about 30 folds on each side of a limb of the gastric cross, instead of 17 as in S. mcrlcnsn. These folds of the genital glands vary greatly in number and increase with age in the Atlantic Stmn-op/wni; they afford therefore an insufficiently definite criterion upon which to base specific distinctions.

Cubaia gemmifera. .s. ulinnema gcmmifera, KISHINOUYE, 1910, Journal College of Sci., Tokyo, vol. 27, art. 9, p. 31, plate 5, figs. 32, 33.

This appears to be an immature Cubaia. The largest of Kishinouye 's specimens was 4 mm. wide and medusiform buds were beginning to develop upon its gonads. The distal ends of the tentacles beyond the adhesive disks are longer than in any species of this genus hitherto described. The manubrium is light red with brown mouth. Of the 16 tentacles, 8 were with "suckers" and 8 smaller ones were without them. 8 lithocysts. Entoderm at base of tentacles greenish and in the distal parts reddish. Found at'Misaki, Japan, in winter.

Craspedacusta sowerbii Lankester (see page 363, Vol. II). C.ras/teJacusta sowerbii, Decisions of International Commission on Zool. Nomenclature, 1910, Science, vol. 31, p. 150.

The International Commission on Zoological Nomenclature publishes its unanimous decision that the name of this medusa is Craspedacusta sowerbii Lankester, not Limnocodium victoria Allman.

726 MEDUS.E OF THE WORLD.

Microhydra ryderi (see page 366, Vol. II).

Microhvdra ryderi, GOETTE, 1908, Mitt, philomath. Gesell., Strassburg, Bd. 4, Jahrg. 16, p. 35, i taf.

Goette records the finding of this hydroid in the neighborhood of Strassburg.. Hitherto it has been known only from Tacony Creek near Philadelphia. Unfortunately I have not been able to see his paper.

Genus Limnocnida (see page 370, Vol. II).

Litnnocnida, GRAVIER, 1908, La Meduse du Tanganyika et du Victoria Nyanza. Sa dispersion en Afrique, Result. Scientifiques voyages en Afrique Edouard Foa, Paris, pp. 601-611.

Gravier gives an account of the dispersion of this genus in Central Africa.

jEgina citrea (see page 451, Vol. II). JEgina pt-tttamrra, KISHINOUYE, 1910, Journ. College of Sci., Tokyo, vol. 27, art. 9, p. 32, plate 5, fig. 34.

This is a 5-rayed JEgina citrea from Misaki and Suruga, Japan, in winter. Vanhoffen, 1908, called attention to the frequent occurrence of 5-rayed aberrations of jEginn. Kish- inouye's medusa is about 20 mm. wide and 10 mm. high, with thick gelatinous hell having a flat top and sloping sides. The mouth is a simple round opening and the 10 genital sacs are nearly quadrate. The 5 tentacles are each about twice as long as the bell-radius. Color ( ?)

SCYPHOMEDUSjE. Carybdea rastonii (see page 508, Vol. III).

Charybdea mora, KISHINOUYE, 1910, Journ. College of Sci., Univ. of Tokyo, vol. 27, art. 9, p. 6, plate I, figs. 4-9.

This form from Japan appears lo be identical with C. rastonn of the Pacific. It may possibly be distinguished, however, as a local variety by the large nettling wans over its exumbrella and its relatively long pedalia, these being about two-fifths as long as the height of the umbrella. I have, however, seen specimens of C. rastonii with pedalia one-third as long as the bell-height.

Carybdea alata (see page 508, Vol. III).

Tarnova vintlenla, KISHINOUYE, 1910, Journal College of Sci., University Tokyo, vol. 27, art. 9, p. 6, plate l, figs. 4-9.

This form, from the Inland Sea of Japan, is apparently identical with C. alata. Kish- inouye describes large specimens 100 mm. high and 60 mm. wide. He finds from 6 to 8 dendritic velar canals in each quadrant, whereas I have not seen more than 6 in specimens of C. alata. A variation of this sort may be expected, however, in specimens of such great size as those found by Kishinouye.

Haliclystus octoradiatus (see page 534, Vol. III).

Halictystus odoradiatus, WIETRZYKOWSKI, 1909, Comptes Rendus Acad. des Sci., Paris, tome 149, p. 746 (development).

Wietrzykowski gives the best account yet published of the early stages of Haltclystus. The planula is about ii6/< long, iS/< wide. The ectoderm forms a continuous sac of flat, hexagonal cells, apparently without cilia. There are generally about 16 entodermal cells arranged in a single row. After I to 4 days of free lite, the planula; settle down upon their anterior ends and become hemispherical. They are apt to settle down in clusters and feed upon Nuuplius larvae, which they capture by means of their nematocysts. The mouth breaks through by the perforation of the ectodermal sac at the summit of the larva. The larva then gradually becomes vaguely 4-lobed and about 150;". in diameter, and a tentacula- form bud develops at the summit of each of the 4 lobes. These buds become detached and resemble the original planula, which developed from the egg, and go through developmental stages similar to those of the mother-larva, fixing themselves by their anterior ends and in turn giving rise to buds, as did their mother.

At the time of formation of the primary buds, one sees a well-developed mvagination of a glandular character at the center of the adherent surface of the larva. This is the beginning of the pedal zone. The body then elongates, becoming filiform, and ihen 2 tentacles, 180° apart and exactly similar in structure to the knobbed tentacles of the adult, develop on opposite

APPENDIX. 727

sides of the mouth. The hypostome then elongates. This stage, with two well-developed tentacles and the hypostome, persists tor several days.

A third tentacle similar to the first two then develops and the three tentacles set them- selves 120° apart, giving the polyp a triradial symmetry. Finally, a founh tentacle develops and the larva has 4 knobbed tentacles 90° apart. No later stages were observed at Roscoff". France, where these studies were undertaken by Wietrzykowski.

Genus Thaumatoscyphus Kishinouye, 1910. Thaumatouypkui, KISHINOUYE, 1910, Journ. College of Sci., Tokyo, vol. 27, art. 9, p. 2.

The type species is Thaumatoscyphus distinctus Kishinouye, from the most northeastern island ot" Chishima, Kurile Islands, Japan.

GENERIC CHARACTERS.

Stauromedusje closely allied to Haliclystus and Stenoscyphus, but with a unitary coronal muscle in the exumbrella; with rudimentary adradial lobes and small, non-adhesive perradial and interradial tentacles. 4 interradial pits in the subumbrella. Peduncle 4-chambered. 8 adradial gonads. Gastric cavity as in Eleutherocarpidae.

This genus is distinguished from all other Stauromedusa; by its exumbrella coronal muscle. This structure is so remarkable, being unknown in any other Scyphomedusae, that its existence requires confirmation, for contraction in preservation may have produced the furrows which Kishinouye observes and believes to be the outlines of strands of muscle fibers. He cut no sections.

Thaumatoscyphus distinctus Kishinouye. Thaiimato!cyl>hus Jiitinclus, KISHINOUYE, 1910, Journ. College of Sci., Tokyo, vol. 27, art. 9, p. 2, plate I, figs. I and 2.

Body goblet-shaped, 30 mm. high. Calyx 15 mm. wide and half as high as height of entire animal. 8 short, adradial lobes, each with about 40 short, captate tentacles growing in a lanceolate tract on the aboral side of each lobe. The tentacles in the proximal part of the tentacular tract have very large, swollen stalks and degenerate distal knobs. These swollen stalks serve as adhesive organs.

The 8 perradial and interradial tentacles are small, cylindrical, and without well-developed distal knobs, although their ends are captate with a median depression at the tip. These tentacles bear black pigment at their bases and along the median line. They are not adhesive organs. The peduncle is more or less quadrate, about as long as the calyx and 4 times as long as wide. It is 4-chambered.

Four deep, interradial mtundibula in the subumbrella. The subumbrella is beset with large, spherical, wart-like clusters of nematocysts, those near the margin and middle pans of the mesogonia being the largest, and about I mm. in diameter.

The coronal muscle is a broad, undivided band, the greater part of which is said to lie in the exumbrella beyond the clusters of tentacles. 4 broad but weakly developed per- radial areas of radial muscles extend from the pyloric region through the stomach wall. The interradial muscles are better developed and extend from the aboral end of the peduncle to the bell-margin. Each interradial muscle band is divided at its distal end into two short limbs which extend to the bases of the adradial clusters of tentacles.

The oesophagus is shoit, somewhat quadrangular, and with deep longitudinal folds. The 4 lips are folded. The central stomach-cavity is long and prismatic and there are 8 adradial rows of simple, long, gastric cirri. There are 8 adradial lanceolate gonads, each con- sisting of 7 or 8 oblong follicles. The abaxial surface of each gonad is black and can be seen through the translucent wall of the body.

Two specimens found in August, 1905, from Shimushiri, Kurile Islands, Japan.

Unfortunately Kishinouye appears to have cut no sections and he bases his statement of the existence of an exumbrella coronal muscle upon the presence of annular folds in the external surface of the body-wall. This appearance may well be due to unnatural contraction in the killing fluid. He studied two preserved specimens. Even if this coronal muscle does not exist, the medusa may still be called Thaumatoscyphus, for it is distinguished from Stenoscyphus by its adradial lobes, and from Haliclystus by having 4 subgenital pits in its subumbrella.

728

MEDUSAE OF THE WORLD.

Genus Parumbrosa Kishinouye, 1910. Parumbrosa, KISHINOUYE, 1910, Journ. College of Sci., Univ. Tokyo, vol. 27, art. 9, p. 19.

The type species is Parumbrosa polylobata Kishinouye from Toyama Bay, Japan.

GENERIC CHARACTERS.

Ulmaridae similar to the genus Discomedusa, but with 64 marginal lappets instead of 32. This genus is evidently derived from Discomedusa by the bifurcation of its marginal lappets.

Parumbrosa polylobata Kishinouye.

Parumbrosa polylobata, KISHINOUYE, 1910, Journ. College of Sci., Univ. Tokyo, vol. 27, art. 9, p. 19, plate 4, figs. 20-23.

Bell 160 mm. in diameter, flat, about 4 times as wide as high. Gelatinous substance of delicate consistency. Exumbrella finely and uniformly graduated. 64 narrow, lanceolate, pointed marginal lappets. 6 velar lobes between every 2 divergent ocular lobes. The velar lobes are 3 times as long as wide, but the ocular lobes are only about halt as long as the velar and about twice as long as wide. Each pair of ocular lobes is, however, mounted upon a common basal projection which causes them to project beyond the contour of the velar lobes.

There are 24 tentacles and 8 sense-organs arranged so that 2 marginal lappets are placed between a tentacle and a sense-organ or between two successive tentacles. The adradial tentacles are the longest. There are powerful muscle fibers on the axial side and transverse bands of nemato- cysts on the abaxial side of each tentacle.

The subumbrella is nearly smooth with weakly developed muscles. The canal-system is as in Discomedusa philippina (see page 607) except that the perradial and interradial canals are less com- plex in their branching and there is but a single, blindly ending side branch from the ring-canal in

each , ; j f ^ • p phlllppma

I r ' r r r

D. philippina may, indeed, be only the young of P. polylobata, and later the 32 lappets may divide to form 64. The large size of the gonads and complex branching of the interradial and perradial canals in D. philippina, however, cause me to hesitate before drawing this conclusion. The bluntly rounded lappets of D. philippina are also very different in shape from the long pointed ones of P. polylobata. In any event P. polylobata was evidently derived philogenetically if not ontogenetically from some such medusa as D. philippina.

The oesophagus of P. polylobata is about as long as the bell-radius, is 4-sided and pris- matic, and the richly folded, lanceolate lips are as long as the mouth-tube. They are thick and keeled along the midrib, and their margins bear numerous minute filaments. The 4 long, narrow gonads are about 5 times as wide as the perradial spaces between them. The medusa is colorless and nearly transparent. It was found in large numbers in a haul of a shrimp-trawl in Toyama Bay, Japan, in June, 1907, from a depth of about 65 fathoms.

Kishinouye gives excellent figures of the medusa.

FOSSIL MEDUSA. Ephyropsites jurassicus von Ammon. Ephyropsites jurassicus, VON AMMON, 1908, Geonostischen Jahreshcft, 1906, Jahrg. 19, p. 169, taf. 3, 2 fign.

This is one of the Coronatce closely allied to Nausithoe. It is from the Upper Jurassic limestone of Pfalzpaint. Bell 150 mm. wide with a distinct annular furrow and a pedal zone 40 mm. wide. 8 tentacles and 8 rhopalia. 16 pedalia in the radii of the tentacles and sense- organs. The tentacular pedalia are twice as wide at the zone of the tentacles as the rhopalar pedalia. A median ridge upon each pedalium, and near the margin on the rhopalar pedalia a pair of short, radiating ridges, each ot which gives off a divergent cross-furrow arising from the inner end of each radiating ridge. There are ring muscles in the subumbrella. A single impression of this medusa was studied by von Ammon.

FIG. vS.-Parun*rosapoIyloba,a After Kishinouye, in Journal College ot ocience University ot iokyo.

INMJKX TO YUUIMK III.

Acalepha deperdita, 715

Acraspeda?, 499

Acraspeditcs antiquus, Jl6

dlginii citrea, fz6

Agassiz, Alexander, acknowledgment to, 499

Agelacrinus lindstromi, 717

Appendix, 7/9

Arcadomyaria, 634

Archirhiza, JI2

aurosa, 712

primordialis, 712 Archirihi/ida?, 633 Astylospongia radiata, 715 Atolla, 561

achillis, 566

alexandri, 566

bairdii, 56}

forma valdivia:, j6j

chuni, 566

gigantea, 565

verrillii, 567

vjyvillei, $66

forma verriilit, $6"] Atollidx, 561 Atnllites minor, Jl6

zittfli, 716 Atorella, 567

sabglobosa, 568

vankoffeni, 568 Atorelliilcr, 541, 567 Aurelia, 619

aurita, 623

clausa, 628

ccerulea, 623

cnlpota, 623

cruciata, 623

dubia, 623, 627

flavidula, 623

habanensis, 623

japonica, 623

labiata, 628

limhata, 628

maldivensis, 629

tnarginalis, 627

sex-ovalis, 623

solida, 627

vitiana, 623 . turelinte, 6iS Aurellia, 6l<)

nunta, 623

jnrmn marginalis, 627

Jubia, 627

flavidula, 623

labiata, 628

maldivensis, 629

AuTtllia solida, 627

water-content of, 622 Auricoma, 619 Aur sa 630

jurcata, 6jO

Bathotrephis astemides, 717 Bathyluca Solaris, 585 Hiblis, 619 Brachiolophus, 709

collaris, 711 Krooksi-lla alternate, 718

conjusa, 718

rli-natia, ~f.\' Budding in Cyanea, 599; Titniolhydra roscoften-

sis, 622; Cassiopea, 643; Cotylorhiza, 662;

Haliclystus, 726

Calicinaria cyathiformis, 524 Callinema, 612 ornata, 616 Cannorhtza, flj connexa, JIJ

Cannostomitcs multicirrata, Jl6 Cafria, 521, S39 sturdzii, Jjp Carybdea, 505, 506

reactions to light, 509 alata, 508, 5/0, J26 var. granJis, jll var. moseri, 512 var. pyramis, JII aunfera, _•,'/() haplonema, 513 marsupialis, $OJ miirrn\<ana, fI2 rustonil, $08, 726 \ii\mncana, fop Carybdeidis, 501, fo^ t'arduella, 523 Ciissifjficn, 636

andromeda, 6i,f

var. acyclvkl/iu, (>J<> var. malayensis, bty var. maldivensis, 6jp var. zanzibanca, 639 anglica, 703 horhonica, 659 borlasea, 703 canariensis, 659 corallifora, 659 Jcpressa, 649

1'nr. fi, In, 649 dieupliila, 636 forslcalca, 637

71". I

730

INDEX.

Cassiopea frondasa, 641, 6j.J

lunulata, 703

ni,'it,-nsu, 6^.g

ndrosia, 650

ornata, tt-jS

var. digitula, 6jS

pallasii, 647

picta, 649

polypoides, 6j.o

rhizostomoidea, 703

theophila, 636

xamachana, 6j.i Cassiopeida?, 633 Cassiopeja acycloblia, 640

andromeda var. cyclobalia, 640

mertensii var. ndrosia, 650 Catostylida?, 633 Catostylus, 66 J

, i u, i ut us, 66j

mosaicus, 666

ornate/lus, 6jO

orsini, 66g

pal mi pes, 66f

purpurus, 671

stiphropterus, 6jO

stulilnianni, 66g

tngi, 668

tripterus, 6jl

turgescens, 671

vindescens, 6jo

wilkesn, 666 Cephea, 651

aldrovandi, 699

capensis, 703

cephea, 6^

var. comffra, 655 var. durnokuroa, 656

conifera, 654, 655

cyclophora, 652

dumokuroa, 656

forskalea, 654

fusca, 654

mosaica, 666

ocellata, 680

octostyla, 6j2

var. coerulescens, 653

papua, 678

papuensis, 678

polychroma, 659

rhizostoma, 710

rhizostomoidea, 654

tuberculata, 659

typhlodendrium, 6jS

vesiculosa, 663

wagneri, 659 Cepheida;, 663, 650 Charybdea, 506

arborifera, 508

hyacinthina, 544

mora, 726

moseri, 512

Charybdea obeliscus, 511

philippina, 512 Chaunostomida?, 633, 650 Chemical composition of Cyanea, 600; Aurellia,

626 Clurodropus, 505, JlS

gorilla, JlS

palmatus, 519 Cluropsalmus, 505, J/J

buitendijki, jif

quadn gains, 516

quadrumanus, J/J

zygonema, JI? Chrysaora, 577

aspilonota, 579

blossevillei, 581

calliparea, 582

chinensis, 582

convoluta, 581

cyclonata, 579

(dodecabostrycha) dubia, 546

fulgida, 581

gaudichaudii, 593

gilberti, 582

helvola, $1

var. calliparea, 582 var. chinensis, $82

heptanema, 579

hysoscella, ^JQ

var. blossevillei, jSl var. fulgida, jSl

blossevillei var. plocamia, 581

isosceles, 579

lactea, 583

lesueurii, 579

macrogona, 579

mediterranea, 579

melanaster, $82

var. gilberti, 582

pleurophora, 579

plocamia, 581

(polybostrycha) helvola, 581

spilhemigona, 579

spilogona, 579 Cladonema radiatum, "J2I Claustra, 619 Cleistocarpidat, j/p Coloring matter, chemical composition of: in

Pelagia, 572; Cyanea, 600; Cassiopea, 637 Collaspidtf, 541, 5<5/ Collaspis, 561

achillis, 566

Commensal plant cells in Scyphomedusce: Cas- siopea, 6^7, 643, 646; Cotylorhiza, 661 ;

Catostylus, 665, 667 Commensalism between Scyphomeduss and fishes:

Sanderia, 591; Cyanea, 609; Cotylorhiza,

663; Catostylus, 667 Commensalism between Scyphomedusje and

shrimp: Cephea, 658 Coronata, 541

INDEX.

731

Coronatcr, 501, J.// Corymorpha nutans, J2O Corynitis = Linvillea, 719 Cotylorhiza, 6j8

ambulacrata, 663 borbonica, 659

tuberculatn, 659

Couthouya, 591

gaudichaudi, 593 Couthouyia, 591

pendula, 593 Crambessa, 664

cruciata, 667

mosaica, 666

palmipes, 667

pictonum, 668

stiphroptera, 670

stuhlmanni, 669

tagi, 668

triptera, 6/1

viridescens, 670 Cramhionf, 6f6

cookii, 677

masttgophora, 6j6 Cramborlii/,a, 672

flagellata, 673 CrasfeJacusta sowerhu, J Craspedotella, 499 Craterloplnis, 521, 538

macrorystis, 538

Crossostoma, 685

anadyomene, 686

Crystals in ectoderm of Nausithoe, 555 Cubaia gcmniifera, 725 Cubomeduste, 507 Cyanea, 595

unnaskiila, 601

arctica, 591, 596, 597

bebringiana, 596

calliparea, 582

capillata, 596

var. fulva, 600 var. nozaku, 601 var. iv if i, n/ur, 600

citrea, 597

ferruginta, 596, 597

fulva, 596, 597, 600

imporcata, 547

lamarckii, 596, 597

muellerianthe, 601

nozakii, 601

postelsii, 596, 597

purpura, 601

rosea, 60 1

Cyanea versicolor, 596, 597, 600 CyaneiJtf, $<)! Cyclomyaria, 634 Cyst-formation in: Cyanea, 599; Taeniolhydra

roscoffensis, 622

Daftylrjntflra, $83 njricana, $88 jerruginnstfr, 588

latt,:I, ,"'V1

longicirra, 589

pacitica var. ferruginaster, 588

quinqueetrrha, 585

var. pacifica, 589 Dactyloidites astcroides, 717

bulbosus, 717 Degenerate medusa-: Staunmu-dusx, 520; Aurclli.i,

622; Taeniolhydra, 622 Depasrrella, 523 Dcpastrilin, 521, 523

i- \-ntliifui tn,; ,"J/

innbai, J2J Desmonema, 591, 595

annasethe, 601

chierchiana, 593

gaudichauJii, 393

rosea, 60 1 Desmostoma, 677

gracile, 68l

])i\rlopment of: Tripedalia, 514; Lucern.n 1.1. 526; llaliclystus, 534, 726; Nausiilmr. 555; Linuche, 559; Pelagia, 573; Chrysaora, 577, 581; Dactylometra, 586; Cyanea, 599; Diplulmaris, 6llj Aurellia, 622, 625; Rhizostomae, 633; Cassiopea, 643; Cotylorhiza, 661; Mastigias, '171); 1'hyllo- rliiza, 684; Rhizostoma, 701; Stomolophus, 710

Dianaea cyanella, 574 Diplocraspedon, 619

limbata, 628

Diplopilus couthouyi, 654 Dtplulmaris, 609

untur, tii ,1, 6lO DiscomeJusa, 606

lohata, 607

philippina, 607 Discomedusae, 541, 569 Donacostoma, 604

woodii, 604 Drvmonema, 603

cordelio, 603

Jalmatina, 603

gorgo, 604

Edible medus;i-: Chiropsalmtis, ^\~; Ixliizostoma,

703; Rhopilema, 706 KK-utlieria, 721 EleutkerocarpiJa, ,' / <> Environment, effect of, upon: Dactylometra, 587;

(.Yanea, 599, 600; Darkness upon C'assiopea,

643 1-pbvra. 551

prometor, 551 F.phyridsr, 550 Ephyroides nitafnrmis, ^(i\ Epli \rnpsiil.r, 541. ,,-n

732

INDEX.

Ephyropsis, 553 Ephyropsites jurassicus, 728 Eucrambessa, 677

miilleri, 679

Eulithota fasciculata, Jl6 Eupilema, /op

scapulare, /op Evagora, 619 Excretory system of Atolla, 561

Favonia sulcata, 723

nipponica, 723 Floresca, 6oj

pallada, 605

parthcnia, 605 Floscula, 605

pandora, 606

promethea, 605 Flosculidae, 604 Fossil Medusa, 715

Grafting in Cassiopea, 646

Habits of Medusae: Creeping habits of the planula

of Lucernaria, 500, 526; egg-laying and

swimming habits of Linuche, 559; feeding

habits of Chrysaora, 581; of Cyanea, 600; of

Cassiopea 637, 647, 648; Cotylorhiza, 661 Heccaedecomma, 612

ambiguum, 615 Haliclystus, 521, 531

antarcttcus, 536

auricula, 532

kerguelensis, 536

octoraJiatus, 53^, 726

salpinx, 535

stfjnegeri, 535

tenuis, 532 Halicyathus, 536

lagena, 537 Halimocyathus, 521, 536

lagena, S37

platypus, 537 Halipetasus, 651

scaber, 652 Haplorhiza, 7/3

punctata, 7/3

simplex, 713 Hermaphroditism of: Chrysaora, 581; Pseudo-

rhiza, 683

Hidroticus rufus, 680 Himantostoma, 693

flagellata, 695

lorifera, 694

var. pacifica, 695 Holigocladodes lunulatus, 703 Homopnensis frondosa, 663

Kuragea, 589

depressa, 589

Kishinouyea, 521, 537 nagatensts, JJI

Laodicea, 719 Laoiira Cambria, /// Leonura, 696 leptura, 696 terminalis, 696 Leptobrachia, 696 hptopus, 696 lorifera, 694

Leptobrachidae, 633, 691 Limnocnida, 726 Limnocodium, 725 Linerges, 557 aquila, 560

draco, 560

mercurius, 558

pegasus, 558 Linergidae, 550 Liniscus, 557

cyamopterus, 558

ornithopterus, 558

sandalopterus, 558 Linuche, 557

aquila, j6o

unguiculaia, JjS

vesiculata, 558 Linvillea, 7/0 Lipkea, 521, 539

ruspohana, $40 Lizzia shimiko, 722 Lobocrocis blossevillei, 581 Lobonema, 631, 6SS

smithn, 689 Loborhiza, 664

ornatella, 670 Lorifera, 693

arabica, 694

flagellata, 695

lorifera, 694.

var. pacifica, 695 Lucernaria, 521, 526

auricula, 532, 534, 537

australis, 530

bathyphiia, 530

campanulata, 530

convolutus, 530

cyathiformis, 524

fabricii, 537 Lucernaria haeckeh, $29

infundibulum, 529

kiikenthali, 529

octoradiata, 534

platypus, 537

pyramidalis ( ?)*, 528

quadricornts, $2J

salpinx, 535

typica, 537 walteri, 529 Lucernaridae, 519

INDEX.

Lucernosa, 526

bathyphila, 530

haeckeli, 529

kiikenthali, 529

walteri, 529 Lychnorhtza, 6j2

bartschi, 674.

flagellata, 673

lucerna, 673 Lychnorhizithe, 633

Manania, 536

auricula, 537 Marsupialida?, 504

Mastigtas, 677

grafile, 68 1

o

ocelltita, 6So orsini, 669 pantherina, 681

papua, 678, 68 1

var. physophora, 678

rosea, 68 1

papua var. siboga, 679, 680

var. siderea, 679 physophora, 678 Mastygias, 677 mulleri, 679 papua, 678 siderea, 679 Medora, 591, 595 capensis, 593 Medusa, 619

andromeda, 637 aurita, 623 bleu, 703 capillata, 596 cephea, 652, 654 corona, 703 frondosa, 647 hysoscella, 579

marsupialis, 507

noctiluca, 572

octopus, 703

octostyla, 652, 654

panopyra, 575

pelagica, 574

pulmo, 699

stc-lligera, 607

tuber, 659

tuberculata, 659

unguiculata, 558 Medustna, 7/7

costata, 619, 7/7

deperdita, 7/5

geryontdes, 7/7

prince ps, 715

radiata, 715 Mcdusites antiquus, 716

costatus, 717

depcrditus, 715

favosus, 715

Vledusites lindstromi, 717

princeps, 715

radiatus, 715 Vlelanaster, 577

mcnensii, 582 Vlelusina, 604

formosa, 597 Micrrjh\Jra ryderi, 726 Vlicrostylus, 651 Vlonocraspedon, 619 Vlonorhiza, 682

haeckelii, 683 Myogramma speciosutn, fl6

^auphanta, 553

albatross!, 555, 557

challengeri, 556

polaris, 554

vettoris pisani, 554 Nauphantopsis, 548

diomedeee, 54$ Nausicaa, 553

phxacum, 556 Nausithoe, 553

albatrossn, 557

albida, 554

chalhngeri, 556

clausi, 556

marginata, 554

picta, 557

punctata, 55^

rubra, 557 Nectophilema, 704

verrillii, 707 Nftnopsis dofleini, 725 Neopelagia eximia, 590 Nervous system of: Lucernaria, 526; Rhizostoma,

702 Netrostoma, 651

ccerulescens, 653

dumokuroa, 656

typhlodendrium, 658

Obflia congdonif 725 Octogonia, 553 Ocyroe, 619 Orithyia lutea, 703 Orythia incolor, 663

Palfphyra, 5J/

antiqua, 551

indica, 553

pelagica, 552

primigcnia, 55' Paraphyllina, $49

intermedia, 549 Paraph yttinida, 541, 548 Paraph \llites distinctus, 5^9, 715 Parumbrosa, 605, JzS

pol \Iobata, "J2$

734

INDEX.

Patera, 604

cerebriformis, 604 Pelagia, $jo

crassa, 576

var. sublaevts, tjj6

cyanella, 574, 576

denticulata, 576

discoidea, 576

ftaveola, 576

neglecta, 574

nocttluca, $J2

var, neglecta, 574

panopyra, 575

var. placenta, 575

papillata, 576

perla, 576

phosphora, 576

placenta, 575

quinquecirrha, 585

tahitiana, 576

unguiculata, 558 Pelagidtf, 569 Pelagothuria, 499 Pennaria tiarella, J2O Period fa, 5+1

campana, 542

quadrigata, 542

tetralina, 54.2 Pericrypta, 541

campana, 542 Periphema, 543 Peromedusae, 541 Periphylla, 543

dodecalostrycha, 549

humilis, 546

hyacinthina, 544.

forma Jodecalostrycha, 546 forma regina, 546

mirabilis, 546 Perirhiza, 561

nematophora, 654 Periphyllida, 547 Periphyllopsis, 543

brauen, 54.6 Phacellophora, 6l2

ambtgua, 613, 6/5

camtschatica, 613

ornata, 616

sicula, 613 Phanerocarpae, 499 Philogeny of Rhizostoma;, 663 Phyllorhiza, 684.

punctata, 684 Pilema, 698

capense, 703

clavigera, 706

corona, 703

octopus, 703

pulmo, 699

stylonectes, 703

Polyclonia, 636, 647

frondosa, 647

theophila, 636

Polyorchis karajutoensis, 723 Polyrhiza, 66 J

cephea, 654

vesiculosa, 663 Poralia, 6l"f

rujescens, 6lJ Potta marina, 699 Preoccupied generic names, 719 Procharagma prototypus, 508 Procharybdis, 505, 506

tetraptera, jo6 Procyanea, 595 Protolyellia princeps, 715 Pseudoclytia pentata, 619 Pseudorhiza, 682

aurosa, 682

haeckeht, 683

thocambaui, 678 Pulsation in: Scyphomedusae, 503; Aurellia, 620;

Cassiopea, 637, 645; Rhizostoma, 701;

Rhisoztomas, 632; Cotylorhiza, 661

Radiomyaria, 634, 650 Rathkea octopunctata, J22

•uar. grata, 722

Regeneration in: Stauromedusae, 522; Haliclys- tus, 532; Craterlophus, 538; Cassiopea, 637, 646; Rhizostomae, 632; Rhizostoma, 702 Rhacopilus, 664 cruciatus, 667 cyanolobatus, 667 Rhizostoma, 6gS

aldrovandi, 699 brachyra, 692 capensis, 703 coeruleum, 703 corona, 703 cuvieri, 699, 703 fulgidum, 581 hispidum, 706 leptopus, 696 lonfera, 694 lutea, 703 mosaica, 666 pulmo, 699

var. capensis, 703

var. corona, 703

var. lutea, 703

var. octopus, 703 rosea, 68 1 sepioides, 703 trigona, 663 Rhizostomif, 501, 631

relationships of, 500 Rhizostomata, 631

dichotama, 634, 650 lonfera, 635, 691 pinnata, 634, 635

INDEX.

735

Rhizostomata scapulata, 635, 6i)"J

sun fill, in, 635, 712

triptera, 634, 66j Khi/.ostomidx, 631, 633, 697 Rhizostomites aJmirandus, 718 Rhopilema, ~<'-f

isculenta, 704

hispidum, 706

rhopalophora, 7°4

verri/lii, 707

verrucosa, 7°6

Sandena, 590

malayensis, jt/o Sarsin japoniea, 720

rosuna, 720

Scyphomedus;e: development of, j.gg, 501; geo- graphical distribution, 501; reactions to light, 509; relationship to Hydromedusae and to Actiniana, 502 Sema^ostomata, 569 Semitostomeit, 501, 569 Semtfostomitt-s zittfli, fl6 Slabberia=Dipurena, 719 Semostomae, 569 Spatangopsis costata, 717 SpirofoJon saltatrtx, f2j. Spongico/a fistularis, 553, JJ^ Stauromeduste, 501, J/p Staurophora mertensii, J2$ Steganopthalmae, 499 Stenoptycha, 595 Stenoscyphidz, 525 Stenoscyphu:, 521, 524 hexaraJiatus, 525 mabai, 525 mirabilis, 553, 554 Stlienoma, 611 albida, 61 1 Sthenomna, 611 Srings caused by medusae, 690 Stomolophid;p, 633, 697 Stomolophus, JO() agaricus, 710 chunii, 710 meleagris, JIO

var. fritillnrifi, 71 1 Stntnutonema reticulatum, 71 j. Stylorhiza, 651 octostyla, 652 polystyla, 652

Swarms of Medusae: Carybdea, 511; Linuche 559, 560; Cyanea, 600; Cassiopea, 643 Cephea, 657; Catostylus, 665, 667; Stomo- lophus, 711; Haliclystus, 726

Taeniolhydra roscoffensis, 622 Tamoya, 505, 5/2

h/iplonema, ^/J

prismatica, 513

punctata, 509

famoya quadrumanus, 515

virulenta, 726 Tessera, 522

princeps, 522

«ypus. 523

Tesserantha, $22

connectens, 523 Tesseraria, 521, 522

scyphomeda, 523 Thaitmatoscyphus, 7%J

distinctus, 727 Tysanostoma, 6yi

denscrispum, 692

thysanura, 6g2 Toreuma, 635

dieitphila, 636

gegenbauri, 636

thvsanostoma, 636 Toxoclytus, 664

roseus, 68 1

tripterus, 671

turgescens, 671 Tripetialia, 505, J/J

cystophora, 5/4 Turris and Tiara = Clavula, 719 Turritopsis nutricola var. pacifica, 722

pacified, 722

Ulmaridce, 604 Ulmaris, 006, 608

prototypus, 607, 609 Ulmaropsis, 609

antarctica, 610

drygalskii, 610 Umbrosa, 606

lobata, 607 Umbrosintf, 605 Undosa, 608

unJulata, 6o<) Urashimea globosa, 722

macrotentaculata, 722 Urtica marina, 579 Urtica marina — octopedalis, 703

Variations in Medusae: Lucernaria, 530; Hali- clystus, 534; Craterlophus, 538; Dactylo- metra, 583, 584; Sanderia, 591; Aurellia, 619, 626; Cassiopea, 640, 641, 643

Versura, 685

anadyomene, 686 maasi, 687 palmata, 685 pinnata, 686 vesicata, 6S6

Jf'illsia pacifica, 723

Zonephyra, 551 corona, 571 pelagica, 552 zonaria, 552