32G THE MYRMECOPHILOUS COLEOP.TERA 



form ; further, according to the specimens found up to the present, it has 

 made the greatest progresss in the Siebengebirge, and in the South of England, 

 which during ' diluvial ' times remained free from ice, and represents the 

 oldest district for the adaptation of this Dinarda to F. exsecia. Should the 

 process of differentiation which separates D. hagensi from dentata make still 

 further progress elscAvhere, then D. hagensi covild not be included any more in 

 the generic diagnosis of Dinarda, since the keeled border of the elytra of the 

 latter has hitherto been regarded as essential. We must even define the 

 whole group of Dinardini differently, since that keeled border of the elytra 

 formed its most essential character ! ... It is perhaps better to reckon . . . 

 our four two -coloured Dinarda forms as races, rather than as species in the 

 strictest systematic sense. But, in any case, they offer races which stand at 

 different stages in their evolution ; D. dentata and miirkeli, as far as concerns 

 their constancy, have arrived nearer to ' trvie species ' than D. hagensi and 

 'pygmcea.''' 



Some confusion has arisen in our literature on the subject, on account of 

 the early captures of Dinarda all being recorded as dentata. Also the ants 

 with which they occurred were incorrectly noted. D. pygincea was first taken, 

 with us, by Reading near Plymouth in 1857. D. dentata was first captured by 

 F. Smith at Weybridge, with its proper host, F. sanguinea, in 1860. D. 

 miirkeli was recorded by Dillwyn as dentata from Swansea in 1829. It has 

 been stated not to occur farther north than Scarborough, but Hislop took 

 it with F. rufa at Kilhecrankie in 1860 (Zool. 1861, p. 7330). D. hagetisi was 

 first discovered in this country by me at Bournemouth ^ith F. exsecta in 

 1905, and I have since found it with the same ant in the Isle of Wight. Dinarda 

 lays the eggs in the earth, and the larvae may often be found in some numbers 

 in the nests. The copulation is similar to that of Lomecliusa. I have bred 

 three of our species in my observation nests. 



Cetonia jloricola, and Clythra 4:-'piinctata only pass the early stages in the 

 ants' nests. The former seeks the nests to lay her eggs in them, she bores 

 into the hillock, and her body is too hard for the ants to injure her. I have 

 found the larvae in some numbers in nests of F. rufa at Nethy Bridge in the 

 Highlands, and have bred the perfect insect from them in my observation 

 nests. The larva feeds on the vegetable refuse of the nest and constructs a 

 cocoon in which to pupate. It does not use the legs for walking. When 

 placed on a table, or on the floor, it turns over on its back and moves rapidly 

 along by means of the bristles on the back, the legs being held up in the air. 



The latter exhibits mimicry, as it superficially resembles the lady-bird, 

 Coccinella distincta, both species being found on and near the nests of Formica 

 rufa. This is a case of Mullerian mimicry, as I have shown the Clythra to 

 be distasteful to insectivora, and the Coccinellidce are known to be so. The 

 life history of *Clythra 4:-jnmcfata, which I worked out in my observation nest 

 of Formica rufa is briefly as follows : 



When the beetle has emerged from the pupa case in the nest, it escapes 

 with caution, " feigning death," and holding on to twigs when attacked by 



* Trans. Ent. Soc. Lend. 1902, Part I, pp. 11-23, with Plate. 



