ASTEROIDEA OF NORTH PACIFIC AND .VDJACIiXT WATlilW — FISUEB. 247 



the glass and remains so for a long time. This is the attitude of a single ray till all, or nearly all, the 

 pyloric caecum assumes its normal position. 



After one arm is 8Pi)araled, or even when it is going, another may break away. I saw one animal 

 try to break the disk apart after having lost two rays. It took many positions, strained the tissues, and 

 worked for hours, but died before the disk was broken. 



The results of my observations are: The breaking is automatic and is effected by pulling apart or 

 fracture without strain; there is coordination of parts in producing the .separation; tlio tissues relax at 

 the plane of rupture; this i)lane may be near the disk or a variable distance from it on the ray; tho 

 pyloric CKca are always pulled out and much stretched; the break of the cax-um occurs ut tli.- 

 tube connecting the stomach and glandular portion; the pyloric ciecum is generally taken back 

 into the arm; the severed ray may Live more than a week, even under adverse circumstance, without 

 signs of regeneration; and, from my experiments extending over a period of three years, I have found 

 that rays cut at various distances from the disk make disks, mouths, and new rays in about six montlu. 



Family ASTEROPID^ " Fishor, lOOS. 



Goniasteridx Pekrier (part). Revision des Stellerides, 1875, p. 280. 



Goniaslerid.r (part ) and Aslcrinidx (part) Viouier, Squelette des StelK-rides, 1879. 



Gymnaslcriadx Perrier, Mem. sur los Etoiles de Mer, etc., 1884, pp. 165, 229. 



Gymnasleriidx Sladen, Challenger Asteroidea, 1889, p. 355. — Authors generally except Perrier. 



Gymnaslcriidx + Poraniidx Perkier, Expud. sci. du Travailteur et du Talisman, 1894, pp. 



163, 327. 

 Asteropidx Fisher, Smiths. Misc. Coll. (Quarterly), vol. 52 (Xo. 1799;, 1908, p. 90; Zool. Anz., 



vol. 32, 1908, p. 358. 



Phanerozonia with the test covered by a skin or incnibruno, either smootli, 

 granulose, or beset with spinelets; juarginul phitesiirojiiiueiit, more or less overlap- 

 ping, smooth or with a single spine or several marginal spinelets; abactinal skeleton 

 loosely tessellate or reticulate; actinal ])Iates fairly large, in chevrons or in isolated 

 serial arrangement ; papuh« usually in areas never actinal but sometimes inter- 

 marginal; pedicellaria) when present bivalvcd or i)incer-shaped. 



KEY TO THE KNOWN GENERA OK ASTKKol'ID.K. 



a'. Marginal and abactinal plates devoid of spines. 

 6'. Abactinal plates slightly lobed or irregular, tessellated, not forming a reticulum; adambulacral 

 armature: furrow series consisting of two spines; actinal spines one or two; a pair of specially 

 localized pedicellaria; at base of rays on abactinal surface Petriciat> Gray. 



a The change of name is necessitated by the fact that Asterope supersedes Gymruuteria. Although 

 Poraniidce is in the field it has been used only by Perrier in a restricted sense for Porania, Tylasler, itar- 

 pinaster, and Poraniomorpha, which ho regards as belonging to the Spinulosa. To avoid confusion it ia 

 better to retain Aalirope as the type of the family. 



*> Petricia as hero used replacea Asteroptis of authors, but not of MilUer and Troschel. The latter, 

 which was published in 1840, and not in theSj-stemderAsteriden, 1842, as invariably quoted, haa exactly 

 the same signification as Gray's GymnasUria (Dec, 1840), but is in turn antedated by Aslerojx Midler 

 and Troschel, as explained below (next fo<Jtnote). The Archiv fiir Naturgeachichto apf>eare<l in three 

 parta to each volume. The article Ueber die Gattungen der Asterien (.\uszug ausdcm Monatsb. preuss. 

 Akad. Wiss. Berlin, April, 1840), in which Asteropsis is described, was very probably in the beginDin4; 

 of the third part, which would mako the date about September, 1840. The genus ia monolypic, and 

 the name cannot therefore be shifted to Asteropsis lernieina (Laman:k), as haa been done by Perrier 

 (Revision des Stelli^rides, 1875, p. 282) and authors since. Asteropsis is a synonym of AsleToi>e, along 

 with Gymnasteria. Asteropsis remicina (Lamarck) Perrier becomes f'etrieia irrnieina. The genus 

 Petricia Gray (Proc. Zool. Soc., pt. 15, 1847, p. 81) has for type /'. punctata Gray, which equals 

 Asteriaa vemicina Lamarck. 



