HARDWI CKE ' S S CIENCE - G O SSI P. 



77 



serve. These movements accomplished, it retreated 

 within the cup-like tube, assumed the form of a puff- 

 ball, and remained quiescent for some time ; changes, 

 however, were proceeding, but so leisurely and slight 

 they could be detected only by comparison from 

 time to time. 3.10 P.M. the organism was visibly 

 enlarged, the cilia had become arranged parallel to 

 each other and protruded like a small brush, these 

 were shortly afterwards absorbed, and at 4.30 P.M., 

 the partly developed arms were plainly visible ; 

 progress contined to be made through the remainder 

 of the day, but full development had not taken place 

 when observations were suspended for the night. No 

 food had apparently been taken up to this time, but 

 the following morning the form was complete, feeding 

 and progressing rapidly, the development to full size 

 was shortly afterwards attained. These observations 

 were confirmed on many subsequent occasions, the 

 only difference being that of time occupied in the 



Fig. 31. — Resting period. 



Fig. 32. — Appearance at 3.10 p.m. 



changes, sometimes one act would be prolonged and 

 another executed rapidly. 



How soon will reproduction take place ? The 

 following table will supply roughly the answer to this 

 question. I was unable to reduce the time to hours, 

 as on some occasions the young emerged during my 

 absence. 



One born August 23, reproduced August 28 = 5 days, 

 i! 2 5 » .> 3° = 5 » 



„ 25 » » 3 1 = 6 „ 



,, 28 „ September 1 = 4 ,, 



„ 28 „ ,, 6 = 9 „ 



„ 2 9 » » 7 = 9 .» 



An average of 6\ days. In the case of the fourth 

 example the full time between the limits was con- 

 sumed, or in other words a very few more hours 

 would have made this one five days also. Repro- 

 duction went on at the rate of one per day, only on 

 one occasion was the second produced the same day, 

 and here again a slight increase in time would have 

 caused its record to be made the following day. The 

 largest number produced by one individual was five, 



the smallest three, more frequently four completed 

 the progeny. 



Messrs. Hudson and Gosse, in their monograph on 

 these organisms, say: "the male of Stephanocera 

 has not been discovered." Without positively laying 

 claim to have seen one, there was one individual 

 might reasonably be considered a suspect. From its 

 first emergence it was slightly larger than the 

 generality of young forms, one of its sides was 

 more deeply crenulated than usual, and small, dark, 

 globular bodies could be detected therein. A pear- 

 shaped cavity near the angle where the posterior 

 portion rapidly narrows was partly filled with bodies 

 of a similar nature, but these were in rapid motion — 

 spermatozoa? This creature, like many others to be 

 noted further on, was isolated from the first, it never 

 settled clown, but led a wandering life from first to 

 last ; its increase in size was very slight, and its 

 development was arrested at a very early age. It 



Fig- 33. — Development at 4.30JMU 



Ct. 



Fig. 34. — Suspected Male, 

 shaped cavity. 



[a] pear 



Scale — ico3 inch. 



lived for about thirty six-hours, and was never seen 

 to take any food. 



How many generations are produced partheno- 

 genetically ? This question still requires an answer ; 

 until the male has been discovered, and observations 

 start from the congress of sexes, it must wait solution. 

 Young ones isolated immediately they emerged from 

 the ovum, and supplied with water from a source 

 when no other adult forms were present, were traced 

 through four generations. The last members of this 

 family contained ova, but from some cause they did 

 not develop ; and, notwithstanding the conditions 

 were the same as had prevailed all through the course 

 of observation, the creatures died without leaving 

 issue. It was not that their life was cut short by 

 any mishap ; they lived as long as the generality of 

 the tribe. 



From thirteen to fourteen days appeared to be the 

 allotted span of a healthy individual's existence ; 



