5° 



HARJDWICKE'S SCIENCE-GOSSIP. 



formations fossil remains of Hymenoptera have been 

 procured from the Middle Eocene leaf beds of 

 Bournemouth, and the Upper Eocene limestone of 

 the Isle of Wight, those from the latter formation 

 consisting chiefly of ants belonging to the genera 

 Myrmica and Formica. On the Continent the Upper 

 Eocene formations of Aix have yielded fossil saw- 

 flies, the parasitic Ichneumons, and Chalcidiidae, 

 together with various species of wasps and ants. 

 Remains of Hymenoptera have also been found, 

 although only sparsely, in the Lower Miocene forma- 

 tions of Switzerland and Germany : but in the Middle 

 and Upper Miocene divisions represented respectively 

 by the marls of Radoboj in Croatia, and the lacustrine 

 deposit of Oeningen, already noticed so often, they 

 occur in great plenty, comprising chiefly ants, ich- 

 neumons, bees, wasps, and Sphegidre. 



5. Lepidopteva. — This order, the most well-known 

 of our insect relations, is also the most recent of the 

 important orders to appear in geological time. It is 

 true indeed that a fossil wing found in the Stonesfield 

 slate of England some years ago has been described 

 by Mr. Butler as that of a butterfly, which he has 

 named Paleeontina oolitica ; but this classification is 

 not recognised by Mr. Scudder and other entomo- 

 logists, who do not consider the wing to be lepi- 

 dopterous at all, and as there is no sufficient evidence 

 of the existence of flowers — upon which butterflies 

 depend — contemporaneous with this species, it is very 

 probable that the insect has been incorrectly named. 

 Some very fragmentary remains from the Upper 

 Purbeck beds of England have also been assigned to 

 the Lepidoptera ; but these, owing to their very 

 imperfect condition, cannot with certainty be referred 

 to any one order specially. Thus, if the foregoing 

 doubtful specimens be excepted, Professor Heer's 

 dictum, " Lepidoptera make their first appearance at 

 Solenhofen," remains a true statement of what is at 

 present known concerning the antiquity of the order. 

 From that well-known slate formation two interesting 

 lepidopterous insects have been discovered, Sphinx 

 Snelleni, a large hawk-moth somewhat similar to the 

 existing S. convolvuli, and Bombyx antiqua, a noc- 

 turnal or night-flying moth. Another species from 

 the same formation, Pseudosirex Darwini, would 

 appear by its name to have some affinity with the 

 genus Sirex of the Hymenoptera ; but not having 

 seen a description or figure of this species, I cannot 

 speak as to its relationship. It is, however, in the 

 Tertiary strata that remains of Lepidoptera first 

 become anything like general. The Upper Eocene 

 Bembridge beds of the' Isle of Wight have yielded 

 two specimens belonging to the genus Lithosia ; 

 while those of Aix in Provence have supplied us with 

 seven species : — five butterflies belonging to the 

 families Papilionidce, Nymphalidae, and Hesperida:, 

 and two moths, A T octuites deperditus and Pyralitcs 

 obscurits, together with the fossil larva of a butterfly 

 belonging to the Satyridae. An interesting fact 



connected with these fossil lepidoptera from Aix is 

 that in almost every case remains of the plants which 

 in all probability served the larvae for food have been 

 found in the same beds from which the insects were 

 obtained. A beautiful and well-preserved fossil 

 butterfly {Pcrdryas persephone) figured and described 

 by Dr. Dawson, comes to us from the extensive 

 Tertiary deposits of Colorado, U.S., and forms one 

 of the most remarkable examples of fossil insects yet 

 discovered, both on account of the excellent state of 

 its preservation and the divergence it exhibits from 

 living types. It is a valuable contribution of the 

 New World to the geological history of the Lepi- 

 doptera. Returning to Europe, the Lower Miocene 

 lignites or Brown Coal formations of Germany have 

 yielded a fossil butterfly, Vanessa vetula, and a small 

 moth belonging to the Tineina, Nepticula fossilis ; the 

 Middle Miocene marls of Radoboj give us three 

 butterflies and five moths, the latter comprising two 

 Noctuidre, two Geometridae, and one Pyralis ; while 

 the Upper Miocene deposit of Oeningen supplies us 

 with fragments of wings and bodies of a moth of the 

 family Bombycidae, a well-preserved larva of the 

 same family, and a larva sac of Psyche pinula curiously 

 made of pine leaves. These remains complete the 

 list of our fossil Lepidoptera. 



6. Thysanoptera. — This small order, consisting of 

 the Linnaean genus Thrips, is composed of minute 

 insects well known to gardeners from their habit of 

 visiting flowers. A very beautiful fossil specimen, 

 discovered in the Tertiary formations of America, is 

 so exquisitely preserved that the minute fringes of its 

 wings are clearly visible under the microscope. 

 When we consider how rare it must be that all the 

 conditions necessary for the preservation of such 

 minute and fragile insects are present together, we 

 must feel how wonderful it is that any remains of 

 them have been preserved at all, much more so, 

 when a specimen has been preserved in such a perfect 

 manner as this delicate little Thrips. 



Summarising the results already gathered from the 

 discoveries we have so briefly passed in review, we 

 find the oldest orders to be the Neuroptera and 

 Orthoptera, whose larvre in so many cases live under 

 the water ; then follow the hardy Coleoptera and 

 aquatic Ilemiptera, all of which date back to Palaeozoic 

 times. In the Secondary rocks earwigs, two-winged 

 flies, and caddis flies begin to occur, and high up in 

 the Oolitic formations the more highly and specially 

 developed Hymenoptera and Lepidoptera make their 

 first appearance, the latter order, composed wholly 

 of species purely suctorial in their mode of life, only 

 becoming of general occurrence in Tertiary times, 

 when the flowers they visit and fertilise begin to 

 appear also. 



Before concluding I must acknowledge my in- 

 debtedness for the information contained in this and 

 the preceding paper to the admirable works of 

 Professor Heer, Dr. Dawson, and Mr. Scudder ; also 



