. Annals of applied biology. Biology, Economic; Biochemistry. 124 On the Life History of " Wirewonns" their death, no ova have been discovered before the early days of July. From a comparison of the time of hatching of some of the ova with that of the maximum incubation period (which is about one month) it would appear nevertheless that some of the eggs are laid in June. Ova of both A. obscurus and A. sputator have been found in burrows excavated by the beetles in the soil, in one case the burrow appearing to be more or less horizontal, in another vertical. It is possible that this m
. Annals of applied biology. Biology, Economic; Biochemistry. 124 On the Life History of " Wirewonns" their death, no ova have been discovered before the early days of July. From a comparison of the time of hatching of some of the ova with that of the maximum incubation period (which is about one month) it would appear nevertheless that some of the eggs are laid in June. Ova of both A. obscurus and A. sputator have been found in burrows excavated by the beetles in the soil, in one case the burrow appearing to be more or less horizontal, in another vertical. It is possible that this may be commonly the case but the friability of the soil when it is ex- amined renders it uncertain whether the burrow will remain intact. The friability of the soil also makes it difficult to say whether the eggs are always laid in clusters. Certainly this is frequently the case, 52 eggs of A. obscurus having been taken in close proximity, but many have also been taken singly and in twos and threes and these have almost certainly not always been detached from larger clusters. In the case of A. sobrinus, only a few eggs have yet been taken and no clusters were. Fig. 1. Coherent ova of Agriotes sobrinus, Kies. Magn. x 50 approx. found, but in the cases of each of the other two species of Agriotes observed, as well as in that of Athous haenwrrhoidalis, clusters of eggs have been found. The eggs in a cluster do not generally cohere at all fast, and no evidence has been forthcoming that they are in any real sense glued together, or to the soil in which they are laid, by any special material produced by the mother for the purpose, as is the case with some insects. Text-figure 1 is an outline drawing showing three eggs of Agriotes sobrinus which were coherent when dug up from the soil. One of them, which appeared to have cohered to the others in a plane at right angles to their long axes, eventually became detached under manipulation. The actual environmental condition necessary for ov
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