MALACOSTRACA. 435 



in the tissues of the Gerardia, from which it appears that Laura derives a 

 large part of its nourishment. There are 6 pairs of vmiramous thoracic 

 appendages, and a 3-segmented abdomen, ending in a caudal fork (/). Medi- 

 terranean. Dendrogaster * astericola Knipowitsch, parasitic in the body 

 cavity of Echinaster sanguinolentus and Solaster endeca. The greatly 

 developed mantle of the female (of which alone the adult is known) en- 

 closes the body except for a small aperture, and is produced laterally into 

 five irregular lobes, which, as in Laura, contain the ovaries and diverticula 

 of the stomach. The alimentary canal ends blindly. The mouth parts 

 are reduced, and other appendages are absent in the adult. The larva 

 carries a greatly developed antenna consisting of four short stout joints, 

 without a sucker but bearing a long whip-like olfactory appendage. There 

 are 5 pairs of long setose thoracic appendages (the 1st thoracic being 

 absent, according to Glaus) and a long 6-jointed abdomen. White Sea. 

 Petrarca bathyactidis Fowler, in the mesenterial chambers of the coral 

 Batliyactis symmetrica obtained at a depth of 2,300 fathoms, off Japan. 

 The mantle forms a bivalve shell. The abdomen is rudimentary. 

 Hermaphrodite. Synagoga mira Norman, f an external parasite on the 

 surface of the colonies of Antipathes larix Ellis, at Naples, with 6 pairs of 

 biramous thoracic appendages and a well-developed caudal fork. 



Sub-class 2. MALACOSTRACA.J 



The name Malacostraca was given by Aristotle, as explained 

 above (p. 360), to a group of Crustacea now classed in the 

 Decapoda. 



* N. Knipowitsch., Beit. z. Kennt. Ascothoracida. (In Russian, with 

 German abstract.) Tran. Soc. Nat. Petersbourg, T. 23 (1892), p. 134. 



f Br. Ass. Rpt., 1887, p. 86. 



j Besides the works of Latreille, Milne Edwards and Dana com- 

 pare W. E. Leach, Malacostraca podophthalma Britanniae, London, 

 1817-1821. Th. Bell, A History of the British stalk-eyed Crustacea, London, 

 1853. C. Heller, Die Crustaceen des siidlichen Euro-pa. Wien, 1863. 

 C. Spence Bate and J. O. Westwood, A History of the British sessile-eyed 

 Crustacea, vols. I and II, London, 1863-68. G. O. Sars, Hist, naturelle d. 

 Crustaces d'eau douce de Norvege, Christiania, 1867. Id. An account of 

 the Crustacea of Norway, vol. 1, Amphipoda, 1895, vol. 2, Isopoda, 1899, 

 vol. 3, Cumacea, 1900. Y. Delage, L'appareil r circul. des Crustaces 

 Edriopnthalmes marins, Arch. Zool. exp. et gen. I. ix, 1881. Faxon, 

 Selections from Embryological Monographs*; I, Crustacea, Mem. Mus. 

 Comp. Zool. Harvard Coll., Cambridge, Mass., 1882. A. Gerstaecker and 

 A. E. Ortmann, Crustacea Malacostraca in Bronn's Thierreich, Leipzig, 

 1881-1901. J. E. V. Boas, Vervancltschaftsbez. der Malacostraken, 

 Morphol. Jahrb. Bd.VIII (1883), p. 485. E. Korschelt u. K. Heider, op. 

 cit. on p. 342. H. J. Hansen, Zur Morphologic der Gliedmassen u. 

 Mundtheile bei Crustaceen u. Insecten, Zool. Anzeiger, I, xvi. (1893), 

 pp. 193-198 and 201-212. T. R. R. Stebbing, Crustacea, London, 1893. 

 C. Glaus, Neue Beitr. z. Morph. d. Crustaceen, Arb. Zool. Inst. Wien. 

 vi. (1896). W. T. Caiman, On the Classification of the Crustacea Mala- 

 costraca. A. and M. of N. Hist. (1), xiii, 1904. 



For the subdivisions of the Malacostraca here adopted, see the Table 

 of Contents. 



