The Stomatopoda are restricted to shallow waters, and as the small collection which was brought home by the Challenger, and entrusted to me for examination, contains no startling novelties, my first feeling, after my preliminary examination, was disappointment at the absence of any unfamiliar type, but this soon gave way to a feeling of excited interest after the discovery that the material in my hands furnished the most ample opportunities for tracing out, with great completeness, the phylogenetic and ontogenetic history of this small and compact order of Malacostraca. The order Stomatopoda includes about sixty species of adults, and an equal or greater number of larvae, from the tropical, subtropical, and temperate waters of the Atlantic, Pacific, and Intban Oceans. Some of the species, like Gonodactylus chiragra, range over the whole of this area, while others, like Squilla nepa, are distributed over the bottoms between the coast of Chili on the one side and the coasts of China and Africa on the other, or Uke Squilla empusa, between Rhode Island, U.S.A., and Africa. They are usually found in very shallow water, and, with the exception of the specimen of Squilla leptosquilla taken in the trawl by the Challenger in the Celebes Seas from a depth of 115 fathoms, and a specimen of Lysiosquilla armata which S. I. Smith found in the stomach of & Lopholatilus from 120 fathoms, they are all from very moderate depths, and the wide distribution of many of the species is undoubtedly due to the great length of their (ZOOL. CHALL. EXP.-PART XLV.-1886.) Yy 1 2 THE VOYAGE OF H.M.S. CHALLENGER. larval life, during which they swim at the surface and are swept to great distances by the oceanic currents. There are, however, many species which are known from only a single restricted locality, and almost one-fourth of the species which have been described are represented by solitary specimens, and there is therefore every reason to believe that many species, and possibly many genera, are still unknown, and that our knowledge of the group is very incomplete. They are extremely active in their movements and retiring in their habits, and they may remain undiscovered in a locality where they are abundant. A few species are recorded as dwelling in crevices in coral reefs, but most of them are burrowing animals. The living animals which form their prey are captured in the long raptorial claws, and some species, like Squilla empusa, often venture to a great distance from their burrows in their pursuit of prey, and are frequently captured in nets and trawls, although others, such as Lijsiosquilla excavatiix, are the Myrmeleons of the ocean, lying in wait for their prey, covered with sand, with only the tips of their eyes exposed, at the mouths of their very deep burrows, to the bottoms of which they dart at the least alarm. At Beaufort, N.C., Lysiosquilla excavatrix is so abundant that the mouths of several burrows may often be found in shallow water in a square yard of the bottom, yet during the six summers I have passed there, I have obt...
Everts; Zeitf. Wiss. ZooL xxiii. 592: 1873. Taf. xxx. fig. 1). a. Cilia of ciliated disc. 6. Ciliated disc. c. Peristome. d. Vestibule. e. (Esophagus. /. Contractile vesicle, g. Food vacuoles. /;. Endoplast. i. Endosarc. k. Ectosarc. I. Cuticle. in. Axis of stem. Pro. 4. b. This soon develops a crown of cilia around the fixed end of the body, as shown in Fig. 10. c. It then detaches itself from the stem by violent movements, and swims away by means of its cilia. ' UJ LI 1. The cut sections of the radiating tubes ; circular when cut perpendicular to their long axis. 2. The more common kind of triradiate spicules arranged around, and in the spaces between, the tubes. 3. The long needle-like spicules upon the outer surface. 4. Make a sketch of a longitudinal section. b. Examine a transverse section with the same power, and notice : 1. The radiating tubes (Fig. 14, b, 6, b) laid open longitudinally. Each tube is divisible into three regions : (i.) The narrow, inner aperture, through which its cavity communicates with the cloaca. (ii.) The long cylindrical canal, which traverses the sponge-flesh from its outer surface to the cloaca.
No abstract
On the Structure and Development of the Gonophores of a certain Siphonophore belonging to the Order Auronectae (Haeckel). By W. K. BROOKS and E. G. CONKLIN. Among the specimens brought by the U. S. Fisli Commission Steamer Albatross (1887-88) from the Pacific and left with us to be studied was a single specimen of a SiphoiiOjihore, which is probably identical with the genus Rodalia, described by Haeckel in his " Challenger " Report. The interest in this form is the greater since Haeckel regards it as so unlike all other Siphonophores as to necessitate its being placed in an entirely new order, which he calls the Auronectae, or Siphonophores with an Aurophore. But a few specimens, and those badly broken, have ever been obtained, and this fact has led Claus, 1 among others, 2 to donbt whether Haeckel was justified in describing these few fragmentary specimens as the type of a new order. The specimen here described was taken off the Galapagos Islands, in latitude 46' south, longitude 89 42' west, and like all the previously described specimens of this group, is badly mutilated, though in an excellent histological condition. 1 C. Glaus, "On the Organism of the Siphonophora," etc.
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