ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 579 



present iu one species and absent from another which closely 

 resembles it. The fibrillated ajipearance of some of the apj)endag0s is 

 regarded as being due to the coalescence of separate cilia. When the 

 integument is highly differentiated and very distinct from the 

 underlying sarcode, the orifice of the contractile vacuole is re- 

 presented by a permanent and constantly visible pore. The author 

 concludes with some observations on the nucleus and nucleolus, in 

 which lie insists on the fact that the latter is certainly absent from 

 some f(irms, even in those that are multinucleated, and he points out 

 the difficulty which this absence presents to our accepting the views of 

 Balbiani as to tlie mode of conjugation of the Ciliata. 



Trichomonas vaginalis.* — J. Eiinstler has now published the 

 full text of his article on this flagellate, a preliminary notice of which 

 was given a7ite, p. 67. 



Acanthometra hemicompressa.f — Dr. L. Car gives an account of 

 this new Kadiolarian which is characterized as follows : — The 

 spicules are long and thin, pointed at the extremity ; the basal portion 

 is quadrangular, the distal half is circular in transverse section, the 

 proximal half lenticular, the two halves are of equal breadth, and 

 this distinguishes the species from A. compressa ; the spicules are 

 elastic, but the elasticity is not so well marked as in A. elastica ; the 

 basal portion which is inserted into the central capsule is quadrangular 

 and provided with triangular wing-like processes ; it terminates in a 

 fine point ; although these spicules are so clastic they appeared 

 usually to be broken. The central cajjsule is transiiarent, and the 

 distal portion only of the spicules projects outside ; as in other 

 lladiolarians the central capsule contains a number of colourless 

 and yellow cells. In its general characters this species is inter- 

 mediate between A. elastica and A. compressa. 



Orbulina universa.J — The life-history of this foraminifer has 

 been a subject of much discussion. Pourtales and Krohn both observed 

 what was apparently a Globigerina iu the interior of many Orbulime, 

 and came to the conclusion that Orbulina was merely a stage in the 

 life-history of Globigerina ; this opinion was combated by Carpenter, 

 wh(; adduced numerous reasons for rctaiuiiig the two genera Orbulina 

 and Globigerina as defined originally by D'Orbigny. 



C. Schlumberger, in numerous specimens of Orbulina universa 

 dredged during the voyage of the ' Talisman ' from a depth of about 

 2000 fathoms, observed the same phenomenon ; of the smaller examples 

 Korae contained within their cavity a " succession of globular 

 chambers, arranged in a spiral fashion, like those of certain Globi- 

 gerincB," while others did not contain any trace of such a structure ; 

 the very large speciraens also wei"c nearly always emi)ty. 



On examining with care this Globigerina-liko body its " plasmos- 

 tracum " was found to bo extremely tine, and traversed by widely 

 bcattcrcd perforations ; the chambers forming the two first turns of 



• Joiirn. do Micro^r., viii. (1884) pp. 317-31 ('2 pis.). 



t Zfjo). Aiizcig., vii. (IS84) pp. it 1-5. 



j CoiJii>ti,a KcntluB, xcviii. (1884) pp. 1002-42. 



