562 



SYSTEMATIC HISTORY OF THE OFUSOKIA. 



Trichodina Grcwdinella approaches to, aiid 

 comes in contact with, its teutaciila, it 

 is immediately taken prisoner, ceases to 

 vibrate, and stretches out its cilia back- 

 wards. On the whole, this species re- 

 sembles Acineta; but Ehrenberg sup- 

 posed it to possess a discharging orifice, 

 though its situation is unknown. Found 

 among dust-like matter upon the surface 



of pond-water, " and perhaps," sa^'S Ehr., 

 ^' also in the sea." Diam. 1-430''. 



P. libera (Perty). — Stemless, spherical; 

 colom*less, or faint yellow; periphery 

 smooth; tentacles hyaline, pointed in 

 greater or less number, many very lono-, 

 sometimes very few present, many seen 

 curved. Diam. 1-330". In stale pond- 

 water. 



Claparede and Lachmann have recently (Ann. d. Sc. Nat. 1857) distin- 

 guished a number of species of Podophrya, many of which would be accoimted 

 Acinefce by Stein ; however, they have no capsule like members of that genus. 

 No characters are given. The following are noted: — 1. Podophrya Oy- 

 dopum, parasitic on Cyclops and Lemna3; 2. P. Carchesii, on Carchesium 

 polypinum ; 3. P. quadripartita, the same as the Acineta assigned by Stein 

 to EpistyJis pUcatilis ; 4. P. Pyrum, a large form, pear-shaped, found on 

 Lemna trisulca ; 5. P. cotJmrnata, the diademiform Acineta of Stein ; 6. P. 

 Ferrum-equinum, the Acineta of the same name of Ehr. ; 7. P. Lynghyei, the 

 Acineta Lyngbyei (Ehr.) ; 8. P. , a marine form, with extremely dila- 

 table suckers. 



Genus DENDEOSOMA* (Ehr.). — This includes beings which resemble 

 Actinophrys, supported on a branching pedicle. The base of the thick 

 pedicle or trunk is fixed ; and its divisions bear the animalcules at theii' ex- 

 tremities. In appearance, therefore, it resembles a microscopic Sertularian 

 polype. 



The question ma}^ be raised, if this genus is not the same as Anthophysa 

 (p. 500), misinterpreted in structure ; and if the organisms terminating the 

 branches are not Uvellce instead of Actinophrydes. 



Dendrosoma radians. — Corpuscles I tentacula; disposed on a soft, smooth, and 

 (animalcules) conical, furnished -u-ith | alternately branched stem. At Berlin. 



Genus EPHELOTA (Wright). — Similar to Podophrya ; but the tentacles, 

 instead of being capitate, are pointed, and form a wreath or circlet. They 

 seem also to be either slightly contractile or retractile, or only flexible. 

 Pedicle composed of a cortical matter or integument, and a medullaiy or 

 contained substance. 



formed of circular fibres passing at right 

 angles to the fibres of the medulla, which 

 cortical fibres are absent in E. coronata. 

 E. coronata (Wright). — Body consists 

 of a short cylinder of densely granidar 

 sarcode, slightly enlarged above and be- 

 low, so as to resemble the circlet of a 

 crown. It is surmoimted by a circle of 

 thick, acuminate and radiating tentacles, 

 which are capable of being slowly cm-ved 

 inwards, but cannot be contracted. They 

 remain stifliy extended when the animal 

 is immersed in alcohol. The structure of 

 the tentacles. I believe, is imique. Under 

 high microscopic power they are seen to 

 consist of a bundle or framework of fine 

 parallel rods of horny (?) texture, imbed- 

 ded in soft contractile sarcode. The more 

 central rods of the bundle protrude con- 

 tinuallv beyond those exterior to them, 



Ephelota ajncuhsa. — Body vase- or 

 cup-shaped, expanded at top and set 

 round with several circlets of numerous 

 pointed tentacles ; abruptly thickened to- 

 wards the base. The tentacles, which 

 are ahvays in more than one row, enjoy 

 little motion, curve themselves forward 

 occasionally, and are slowly retracted at 

 times. Pedicle stout. Found parasitic 

 on Sertularia ; by Dr. Wright on Corijne. 



It diff'ers from JE". coronata in having the 

 body wider than the stem, more cup- 

 shaped and elongated, and the tentacles j 

 more irregular, soft, retractile, and unsup- 

 ported by the solid matter which occurs 

 in the interior of those of the species 

 named. It is especially distinguished by 

 the shape and structure of the stem, 

 which is of nearly equal diameter through - 

 out, and encloses a cortical substance 



