ZOOLOGY AND BOTANY, MIOEOSCOPY, ETC. 597 



* Challenger ' Sponges. — Messrs. S. O. Eidley and A. Dendy report * 

 on the Monaxonid Sponges collected by H.M.S. ' Challenger.' In the in- 

 troduction a full account is given of the spicules. Gladorliiza tridentata 

 (from a depth of 1600 fathoms) has imbedded in its soft tissues a large 

 number of small yellow globular bodies ; each of these consists of a 

 central, more deeply staining and granular portion which is surrounded 

 by and imbedded in a matrix of faintly staining, perfectly hyaline, 

 ground substance. Other peculiar cup-shaped bodies occur towards the 

 periphery of the sponge, and the authors suggest that the whole structure 

 may be phosphorescent, and serve to attract the minute organisms on 

 which the sponge feeds. The order Monaxonida is divided into the two 

 suborders Halichondrina and Clavulina ; the former consists of the 

 Homorhaphid^, Heterorhaphidse, Desmacidonidse, and Axinellidte ; tha 

 latter of the Suberitid^ and Spirastrellidae. More than two hundred 

 species or well-marked varieties are described, twenty-four of which 

 were found at depths between one and two thousand fathoms ; those from 

 great depths are, almost without exception, beautifully symmetrical, 

 while shallow-water forms are characteristically shapeless, or at most 

 digitate or ramose. The Hexactinellida f are reported on by Prof. 

 F. E. Schulze, who gives an atlas of 104 most beautiful plates. Twenty 

 new genera and sixty-five new species are described ; the greatest depth 

 at which they were found was 2900 fathoms, from which BatJiydorm 

 fimhriatus was taken. 



Protozoa. 



BiitscMi's Protozoa.^ — Since we last gave a notice of this important 

 work parts 35-46 (pp. 1089-1376), with plates 51-71, have been 

 published. The history of the progress of our knowledge of the 

 Infusoria is completed, and a bibliography containing 822 titles is 

 appended. The account of the first sub-class — that of the Ciliata — is 

 commenced, its general morphology being first dealt with ; this is 

 followed by descriptions of the ectoplasm and its differentiations, in 

 which, inter alia, the interesting question of the striation sometimes 

 observed is discussed ; the locomotor organs of the ectoplasm and allied 

 structures are next described, and here, in addition to pseudopodia and 

 tentacular processes, cirri, membranellae, and undulating membranes are 

 noticed. Part 46 breaks off in the midst of an account of the mouth 

 and gullet considered as differentiations of the ectoplasm. 



Multinucleate Infusoria.§— Prof. A. Gruber describes the various 

 multinucleate Infusoria which he has observed, and gives a detailed 

 account of the division of Solosticha scutellum. When the process 

 begins the numerous small nuclei unite ; beside the large nucleus thus 

 formed a small accessory nucleus for the first time appears ; the latter 

 Gruber believes to be due to the fusion of extremely small previously 

 invisible elements. The accessory body divides first, then the large 

 nucleus. All the divisions of the latter exhibit nuclear figures pre- 

 viously described. A transverse constriction of the body becomes more 

 and more marked. Each half contains the division products of large and 



* Keports of H.M.S. ' Challenger,' Monaxonida, lix. (1887) 273 pp., 51 pis. 



t Eeports of H.M.S. 'Challenger,' Hexactinellida, llii. (1887) 513 pp., 104 pis. 

 X Bronn's ' Klassen u. Ordnungen. Protozoa,' by Dr. 0. BLitschli, parts 35-46, 

 Leipzig and Heidelberg, 1887-8. 



§ Ber. Nat. Gesell. Freiburg, iii. (1888) pp. 58-69 (2 pis.). 

 1888. 2 T 



