296 Miscellaneous. 



aberrant types ; the Crinoids are aberrant Apiocrinida3, Pentacnm, 

 or modified Comatulae ; the Stellerida, except the Brisingce, are 

 Goniasteridne or Astropectinidae; the Spatangoid urchins and those 

 with flexible tests predominate over the regular urchins, which arc 

 the most ancient forms ; the Holothuridse are those with a ventral 

 sole and with bilateral symmetry as marked as in an Annelid ; the 

 Decapod Crustacea are the most numerous ; and among the- JEol- 

 lusea the most ancient forms, the Cephalopoda and Pteropoda, are 

 almost entirely deficient. All these forms are abundantly repre- 

 sented in the shallower zones and at the surface. The conclusion 

 drawn from these facts by the author is that the abyssal fauna is, 

 for the most part at any rate, a fauna which has descended from 

 the littoral and other shallow regions, and become acclimatized at 

 the great depths. The conditions of existence becoming more and 

 more constant or even perfectly uniform in the deeper regions, 

 species of the most various derivations, when they had once attained 

 a certain zone, could spread everywhere ; and thus we explain at 

 once how the fauna of the great depths presents a very constant 

 composition in all regions of the globe, but at the same time includes 

 various species the analogues of which occur in the sublittoral 

 regions of both cold and hot climates. — Comptes Rendus, March 12, 

 1883, p. 725. 



ActinospTicerium Eichhoniri . 



Prof. Leidy remarked that he had noticed in an aquarium what 

 appeared to be eggs adherent to the edges of the leaves of Vallis- 

 neria, from the Schuylkill river. On examining the egg-like bodies 

 with a lens, they were observed to be covered with delicate rays. 

 On transferring some of the bodies to the field of the microscope, 

 they proved to be giant specimens of the larger sun animalcule 

 Actinosphceriam Eichhont.il. They measured from three fourths to 

 one millimetre in diameter, independent of the rays, which extended 

 from one fourth to half a millimetre more. One of the smaller in- 

 dividuals contained four water-fleas, Daphnias, a third of a milli- 

 metre long ; and one of the larger contained six of these. The Acti- 





nospl iq mum appears to be tenacious of life, several specimens havin 

 been retained alive and in good condition for three days in a drop of 

 water in an animalcule cage. They had discharged the Daphnias, 

 but retained their original size. One of oval form measured 1 mil- 

 lim. long by 0*75 millim. broad. The smaller ones measured 0*75 

 millim. in diameter. After another day they appeared in good con- 

 dition; but the rays were contracted so is to be about half the ori- 

 ginal length, and many had a minute granular ball at the end, appa- 

 rently effete matter thrown off from them. At this time the ani- 

 malcules were returned to the aquarium. — Proc. Acad. Nat ISci. 

 Philad., Oct. 31, 1882, p. 260. 







