ZOOLOaY AND BOTANY, MICROSCOPY, ETC. 105 



tinctly differentiated or doubly refractive. The different phases are dis- 

 cussed at length, but the problems of length, transition, and conditions are 

 still unsolved. Some notes on the reproductive phenomena in Acantho- 

 metridae are then added. 



IV. Systematic. — The Sphserozoida are distinguished from the CoUo- 

 sphserida chiefly in these points : in the formation of anisospores in S. the 

 grouped arrangement of the nuclei persists till the spores begin to be 

 formed, vehile in C. it is of a very short duration ; in S. the macro- and 

 micro-spores are formed in the same individual, in C, however, in different 

 individuals ; in S. true extracapsular bodies are formed, but these have 

 never been observed in C. ; on account of these developmental differences, 

 therefore, the two families are distinguished. Since it is impossible to 

 summarize the systematic portion of the work, it must suffice to note the 

 net result. 



SPH^ROZOA. 



Fam. I. SpttaEEOZoiDA. 



Collozoum Hkl. Usually without skeleton, occasionally with isolated 

 spicules. 



1. C. inerme Miill sp. 



2. „ fulvum n. sp. 



3. „ pelagicum Hkl. 



4. „ Mertwigii n. sp. 

 Sphjerozoum Meyen. With sUiceous spicules. 



5. SpJi. pundatum Huxl. sp. 



6. „ neapolitanum Brandt. 



7. „ acuferum Miill. 



8. „ HsecJceli n. sp. 



9. ",', spinulosum Miill. 



Fam II. CoLIiOSPHJERIDA. 



Myxosphsera n. g. Without skeleton. 



10. Myxosph. cserulea Hkl. sp. 

 CollosphsBra Miill. With smooth latticed shell. 



11. Collosph. Huxley i Miill. 



Acrosphsera Hkl. Latticed shell wdth pointed spines. 



12. Acrosph. spinosa Hkl. 



Siphonosphaera Miill. Latticed shell, in which the principal apertures 

 are drawn out into tubes. 



13. SipTionosph. tuhulosa Miill. 



14. „ tenera n. sp. 



New Opalina.* — ^Under the name of Opalina spiculata Herr N. Warpa- 

 chowsky describes a new species of Opalina which is found abundantly in 

 the coelom of young earthworms, and is characterized by the presence of a 

 long spicule which lies in the body, and is about two-thirds of its length. 

 It seems to be most closely allied to 0. prolifera and 0. uncinata. 



Parasites in the Blood of Lizards.f — Prof. B. Danilewsky communi- 

 cates a further report of his continued studies on blood-parasites. Along 

 with M. A. Chalachnikow he has investigated those of lizards. 



Within red blood-corpuscles which exhibited external peculiarities in- 

 tracellular parasites or Hsemocytozoa were found, as in previous cases. Of 

 intracellular forms three types are distinguished — (a) a large, quiescent 



* Bull. Acad. Imp. Sci. St. Petersbourg, Xxx. (1886) pp. 512-4. 

 t Arch. Slav, de Biol., i. (1886) pp. 364-96 (2 pis.). 



