FOR PLEASURE AND PROFIT. 137 



Your next care is tot remove all white eggs. If the 

 have been thoroughly impregnated at spawning these should 

 be few, but there are sure to be some. This advice holds gcod 

 right up to the time of hatching; indeed, most probably, a 

 few white eggs will remain over even after hatching is com- 

 pleted. It is almost needless for me to explain that the white 

 eggs are dead. In removing them be very careful, more espe- 

 cially in the early stages of incubation, not to disturb the sur- 

 rounding fertile eggs. Be sure to remove all white eggs as 

 soon as they are seen ; neglect of this precaution may result 

 in a disastrous attack of byssus commonly called fungus. 

 As a matter of fact, the eggs should be carefully gene ever 

 every day and all white ones removed. Keep the hatching 

 boxes covered with the lids at all times when not engaged 

 upon looking over the eggg. 



Various forms of " egg extractors " have been devised for 

 the purpose of removing the white eggs, but I know of no 

 more simple or perfect instrument than that used at Howie- 

 toun. This I illustrate in Figs. 37 amd 38. Any glass-blower 

 will make you a few of them. They are formed from a length 

 of Jin. (inside measurement) glass tubing, with a swelled and 

 " necked " bulk at one end and a constriction formed at the 

 other. The shape is clearly shown in Fig. 38. Over the bulb 

 end is stretched al piece of indiarubber, and the instrument 

 then has the appearance asi shown in Fig. 37. As explained 

 by Sir James Maitland, pieces of old tobacco pouches make ex- 

 cellent covers for these egg-extractors. They are used in tUo 

 following manneri: The thumb is gently pressal on the india^ 

 rubber; this forms a vacuum in the bulb. Next the extrac- 

 tor is advanced in the water (still retaining pressure on the 

 indiarubber) until the constricted end is immediately over the 

 egg to be extracted. By removing the pressure of the thumb 

 on the indiarubbsr the egg is sucked up and held tight in the 

 constricted end, and is prevented travelling right up the tube 

 by the constriction. If this constriction did not exist there 

 would arise the necessity of removing the indiarubber before 

 the egg could be released from the tube. But witli the con- 



