ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 903 



Asteroidea of the Norwegian North Sea Expedition.* — D. C. 

 Danielsseu and J. Korcu here give in a handsome and connected 

 form, the results of their studies on the starfishes collected by the 

 Norwegian North Sea Expedition, which have been separately 

 published from time to time. The work is illustrated by fifteen 

 plates as beautiful as those in preceding essays by the same natural- 

 ists. Reference is made to the difficulties of diagnosing the species, 

 owing to the paucity of material, or the rarity of specimens for com- 

 parison, or the scattered condition of papers on the grouj}, and their 

 general lack of illustrations. The collection contained 41 species 

 belonging to 20 genera ; of these 11 species and 4 genera are new. 



In face of the views held by various naturalists as to the 

 significance of Prof. Perrier's discovery of Caulaster pedunculatus, it 

 is interesting to note that Danielssen and Keren think that Perrier is 

 correct in supposing that his new form is a connecting link between 

 the Crinoidea and Asteroidea; their observations on their genus 

 Ilyaster confij'm the supposition. In the developmental stages of the 

 Echinodermata the Crinoid represents the oldest and the Asteroid 

 the youngest stages in the process. 



Mimaster, a New Asterid.j — W. Percy Sladen describes a new 

 and magTiificent starfish, Mimaster tizarcU, which is remarkable for 

 presenting indications of affinity to several groups of starfishes. 

 The arrangement and appearance of the paxillte recalls Solaster ; but 

 the skeleton, in place of having its abactinal portion consisting of a 

 closely reticulated calcareous framework, in which the paxillae are 

 borne, has it formed of paxillfe alone, the bases of which are closely 

 placed, and occasionally overlap ; this is the structure which has 

 hitherto been supposed to be distinctive of the Astropectinidfe. 

 Mimaster resembles the Goniasteridae in the adambulacral plates, the 

 ambulacral spines, and the mouth plates ; the ventral plates recall 

 those of the Asterinidce, and have some likeness to the arrangement in 

 the Goniasteridce.. The genus appears to be most closely allied to 

 Badiaster, lately described by Perrier ; but there are striking and 

 important points of difference between them. The present form was 

 collected by the ' Knight Errant ' in the Faeroe Channel at a depth of 

 555 fathoms. 



Amphicyclus, a New Holothurian.J — Prof F. Jeffrey Bell gives 

 an account of a new genus of dendrochirotous Holothurians, for which 

 he proposes the name of Amphicyclus japonicus ; it is remarkable for 

 having the ambulacral suckers arranged in regular rows (stichopod), 

 together with the tentacles in two circles, fourteen in the outer, and 

 ten in the inner ; it seems to be most closely allied to Actiuocucumis, 

 with a stichopod arrangement of suckers and from 18-20 tentacles. 



The author proposes to rearrange the Dendrochirotai, by first 

 taking note of whether the arrangement of suckers is regular 



• 'Den Norskc Nordhavs-Expeditioii 1876-8. XI. AstcroMea.' fol., 1884, 

 118 pp. (1.5 pin.). (In Norwegian and English.) 



t Trans. Koy. Soc. Edin., xxx. (for 1881-2) pp. 579-84 (1 pi.). 

 X Proc. Zooi. Soc. Lend., 1884, pp. 253-8. 



