88 '^P"i' 



which, perhaps, first arrests one's notice in such a survey is the striking 

 disparity between the predominance of species during two successive 

 years in the sanae locality. Take a few instances, drawn from an area 

 of not more than one square mile of pine wood, broken by open heath, 

 where broom, furze, and small birches grow luxuriantly. In 1914 it 

 was impossible to break up any of the scattered dead twigs and small 

 branches of the pine without disclosing Pityogenes bidentatus in pro- 

 fusion, accompanied occasionally by HypopMoeus linearis, which is in 

 some way dependent on it ; later on, Sphaerlestes {Salpingus) aeneus 

 (aeratus olim) was almost equally abundant, and through all that long 

 rainless summer we could be pretty sure, on any evening, of sweeping 

 up at least one or two Triarthron miirlceli, or perhaps Amphicyllis 

 globus, with occasionally its ysly. ferriiginea. Liodes scita (nigrita olim), 

 too, was quite frequent, and in places where the grass was mixed with 

 ling, those two minute Hypocypti, H. seminuluni and H. punctum, were 

 common. It was easy to select individuals of these which would seem 

 to represent series of two distinct species, but intermediate forms were 

 so common that I am disposed to agree with the conclusion suggested 

 by the Eev. W. W. Fowler (Col. Brit. Isls., Vol. II, p. 187) that they 

 are probably forms of one species. During the present year, 1915, 

 however, Scolytidae of all species have been remarkably scarce, and I 

 have not seen a single P. bidentatus, still less its associated Hypophloeus. 

 No S. aeneiis have been observed, and sweeping as persistent as that of 

 last year has resulted in the capture of one Triarthron only, less than 

 a dozen Liodes, no Amphicyllis, and but an occasional Hypocyptus. 



Such differences between the specific abundance of certain species 

 during successive years in the same locality is, of course, well within 

 the experience of all Entomologists ; its cause, often indirect, is usually 

 far too complex for us to unravel or appreciate, but I think in the 

 present instances much may be attributed to the long drought of the 

 late summer of 1914, which, in a dry sandy district such as this, is felt 

 with exceptional severity. 



On the other hand, the present year (1915) has produced in 

 abundance species unnoticed, or rai-e, during its predecessor. Of these, 

 Thanasimus formicariiis, which appeared abundantly in April, and again 

 more sparingly in September, and Tychius venustws, common on the 

 broom, are examples ; and although the Scolytidae were generally very 

 deficient, yet Eccoptogaster {ScolytusJ rugulosus occurred in abundance 

 in the dead boughs of a plum tree, accompanied scantily by LaemopMoevs 

 ater, an association which seems hitherto unnoticed, for this species is 



