274 



HARD WICKE'S SCIENCE- G OSS IP. 



conical posterior portion of the oral fossa into the 

 endoplasm, a narrow channel often there opening to 

 receive and to conduct them, at times, to the posterior 

 part of the body. Bacilli and minute spirilla in their 

 headlong course striking the curved flagellum at any 

 part of its length are, in some strange way, deflected 

 to the oral aperture, and are usually sooner or later 

 engulfed. 



But unless their momentum is sufficient to cany 

 them to the point of insertion of the flagellum within 

 the oral fossa, they will swim out of the aperture, and 

 voluntarily return again and again. This sporting with 

 fate may continue long and be followed by no disas- 

 trous result, unless the bacillus comes in contact with 

 the slightly oblique posterior wall of the oral fossa, 

 when it seems to become helpless ; it then invariably 

 glides forward and into the animalcule's endoplasm. 

 These posterior walls are not membranous and fixed, 

 but soft, and dilatable at the infusorian's will. The 

 creature at intervals makes mimic pharyngeal gulps, 

 but, as a rule, food is not then swallowed ; the 

 bacterial procession is at that time Interrupted. Still 

 the distal end of the curved flagellum lashes the water, 

 the delicate bacilli swarm around the oral aperture ; 

 they hurry in, they hurry out ; singly they pass 

 beyond the fatal orifice, a shining path opens before 

 them, and into the substance of the hungry petalo- 

 monas they enter, to leave it only as granules and 

 shapeless fragments. 



What is the attraction at that mouth-margin which 

 these bacilli shall find so agreeable that, after their 

 sudden slide down the flagellum, they shall there 

 swarm like gnats in the summer sun ? Is there any 

 special attraction ? They may be only following that 

 impulse that leads them to congregate in a cloud 

 around almost any stationary object. And arrived at 

 the rearmost obliquity within that gaping mouth, why 

 not turn and swim again into the open ; why, with- 

 out apparent effort or movement on the infusorian's 

 part, should they slip onward and be engulfed ? 

 There are no minute cilia, or any hidden flagellum to 

 explain the final act. But the short posterior oblique 

 plane leads to the oral aperture proper, and a plausible 

 explanation of the inability of the bacillus to escape 

 from the region may perhaps be found in the ease 

 with which an object can move down an incline, the 

 bacillus being assisted by its own flagella. It is also 

 possible that this adoral plane may be a sensitive 

 surface ; and it may have the power to voluntarily 

 alter its angle of inclination so as to more readily 

 direct the food particles to the mouth, the surface 

 being so minute that the change of position eludes 

 observation. 



Those naturalists who are so fond of dilating on the 

 intelligence of animals, may accept this little creature, 

 the yjljjj inch long, as an example of the superiority 

 of infusorial mind over bacterial matter, and conclude 

 that as the animalcule evidently knows when it 

 arrives at a bacterial region, so does it evidently also 



know that by lying still with permanently opened 

 oral aperture, and with gently throbbing flagellum, 

 those senseless plants will swim in and finally be 

 taken in ; so why go to the trouble and expense of 

 tissue formation to develope contractile lips or pro* 

 trusible pharynx, when experience teaches that bacilli 

 are good, nutritious and easily captured ? Having 

 once accidentally taken a single bacillus by not trying, 

 and finding it agreeable to continue to capture bacilli 

 in the same way for all time, is it not an evidence of 

 intelligence ? But the intellect of Petalomonas 

 carinata must be left to the reader for further inves- 

 tigation. 



The figure is a diagram of the anterior part of the 

 neutral surface, showing the position of the flagellum 

 while the infusorian is taking food. 



Trenton, New Jersey, U.S.A. 



ASTRONOMY AND METEOROLOGY. 

 By John Browning, F.R.A.S. 



ANEW comet was discovered on the 5th of 

 October by Mr. Barnard, at Roshville, Tenes- 

 see. It is bright and round, and when discovered it 

 was in the constellation Sextans, moving towards 

 the south-eastern part of Leo. It is approaching the 

 earth, so that its brightness at the end of October 

 was about three times as great, and at the end of 

 November about ten times as at the time of its 

 discovery. 



Professor C. H. F. Peters has discovered another 

 small planet at Clinton, N.Y. ; and Dr. J. Palisa 

 discovered two at Vienna, on the 3rd of November. 

 Two hundred and sixty-three of these bodies are now 

 known ; of these Professor Peters has discovered 

 forty-five, and Dr. Palisa fifty-seven. 



Professor Kruger states that the perihelion passage 

 of Barnard's comet will take place on the 16th of 

 December, at the distance from the sun cf 0.66 of 

 the earth's mean distance. 



Dr. E. Lamp finds that the comet will be nearest 

 the earth in the first week in December, when it will 

 be twenty-four times as bright as at the time of its 

 discovery. 



The annual report of the Pulkowa Observatory has 

 been issued by Professor Struve. In the physical 

 department, Herr Hasselberg has obtained a large 

 number of photographs of the solar spectrum and 

 determined the position of several new lines which 

 they contain. A new refracting telescope which has 

 an object-glass 30 inches' diameter has been mounted 

 in the observatory. With this it is believed some 

 further changes have been noted in the famous star 

 in the great nebula of Andromeda. 



On December 19th, there will be an occultation 

 of 7 1 (gamma) Virginia, magnitude 2L The disap- 



