A. W. RvMER Roberts 117 



the life history have in some measure been cleared up, it has been felt 

 that these should be put on record without further delay. 



To Dr E. J. Russell, the director of the Station, for the opportunity 

 to carry on the work, also to Mr J. C. F. Fryer and Dr A. D. Imms, in 

 addition to Dr Russell, for suggestions and information at many different 

 points, my hearty thanks must be here expressed. 



METHODS. 



In order to obtain eggs from the parent beetles, grass plants were 

 potted up in small (4 inch) pots and the surface of the pots enclosed by 

 glass cylinders, the tops of which were covered by a piece of butter 

 muslin. The beetles, when available, could be placed in the cage so 

 formed either by removing the muslin covering the top of the glass 

 cylinder, or by removing the whole cylinder, afterwards pressing it 

 down a little into the soil of the pot, when replaced in position. In this 

 manner the beetles were safely enclosed and by keeping the pots in a 

 shady place and watering sufficiently for the needs of the plants, eggs 

 have been obtained from Agriotes obscurus and A. sputator in 1916 and 

 from the same two species, with the addition of Agriotes sobrinus and 

 Athous haemorrhoidalis, in 1918. The pots, after having received their 

 full complement of beetles, were left alone for three or four weeks to 

 allow the beetles time to deposit their eggs without disturbance. 



When it was judged that sufficient time had elapsed, the soil was 

 carefully turned over with the point of a penknife and the eggs (if found) 

 were laid bare. Eiscovery is facilitated if the soil is of a dark colour, is 

 friable and does not contain many grains of sand, which may be mistaken 

 for solitary eggs. 



When eggs were obtained, they were taken into the laboratory and 

 placed on damp soil in watch glasses or similar vessels for further 

 observation. The soil being kept moist, no difficulty was experienced 

 in hatching out the larvae. In some cases it was found necessary to 

 pack the eggs for travel and this was done by transferring them to 

 corked tubes containing fresh, moist, moss. Even when kept in these 

 tubes with a bung of moss to replace the cork, for a fortnight or so, the 

 results were satisfactory in the numbers hatched, though the ova ap- 

 peared to run some risk from moulds which were inclined to spread 

 their hyphae over the moss. 



Beside the eggs which were taken from the pots for examination 

 and observation in the laboratory, others remained and hatched in the 

 soil of the pots. During the autumn of 1916 in view^ of the approaching 



