178 THE entomologist's record. 



The period to which the hibernated earwigs, the parents of the 

 brood, survived was not identical with the experience of the previous 

 year. The view that no adult earwigs are to be found in June was 

 quite true of this locality and the season of 1916. In 1917, a good 

 many survived much longer than in 1916, a result probably due to the 

 remarkably prolonged winter of 1916-1917, so that here, as in many 

 other cases we are familiar with, dates of appearance and disappear- 

 ance vary with the particular seasons and are not by any means 

 dependent merely on the almanac. 



In my jars, for example, a male survived till July 5th, a female 

 till the same date, a male died June 7th, a female on June 2nd, a 

 male on June llth, a female on July 2nd, another on June 2ud, one 

 on June 5th and a male on same date ; others died earlier. As regards 

 the date on which earwigs of the season first mature, an earwig had 

 made a nest and laid eggs by December 12th, 1916. The first of the 

 young brood to become mature did so on May 19th. These were 

 reared in a warm room, and if we recollect that so early a start out of 

 doors must be very rare, and if made, almost certainly with disastrous 

 result, the date of July for the first imagines of the year to appear 

 seems still to stand good. Two or three specimens were met with at 

 large at the end of May and in June. These were no doubt survivors 

 of the previous year's brood. 



The eggs grow very materially during the period of incubation. 

 This must be secured by the imbibition of fluid through the shell. 

 The mother may often be seen moving her eggs, generally as a result 

 of the disturbance due to opening the nest, but she may, when a view 

 can be obtained without alarming her, be seen to be apparently licking 

 them over, whether she supplies them in this way merely with watery 

 fluid or whether it contains also some nutrient material, I cannot say, 

 this process may be most readily observed in one of Mr. Main's ob- 

 servation cages. 



The following are actual measurements — 



Eggs laid April 14th measured 1.07mm. long and 0.8mm. wide. 



On the 24:th l-15mm. long, 0-78mm. wide ; 



On May 1st l-35mm. long, l-04mm. wide ; 



And on 5th l-38mm. long, l-07mm. wide. 



Hatched llth. 



Another batch laid — 



On March 28th measured l'16mm. long, 0*8mm. wide ; 



On April 14th l-27mm. long, 0-93mm. wide ; 



On 23rd l-47mm. long, l-05mm. wide; 



On 29th, ready to hatch, l-56mm. long, l-3mm. wide. 



Another series shows eggs laid 26th or 27th April — 



On 29th measured 1-Omm. xO.75 mm., and 0.95mm. xO.77 mm. ; 



On May 5th l-08mm. x 0*81mm. was the measurement of each 

 of two eggs ; 



On May llth l-38mm. x l-07mm., i.e., five days before hatching, 

 which occurred on the 16th, the measurement happened to be the 

 same as at six days before hatching in the first batch. The increase 

 here would be almost exactly three-fold. 



The first of these batches, like the last, was just missed for a last 

 measurement before hatching, and so the full increase in size is not 

 shown. The second set of measurements therefore gives a better 



