This natural group, which was distributed by Fabricius, has 

 been formed into a genus by Latreille, but has never been 

 described as British. Like the rest of the Ichneumonidae 

 these small insects deposit their eggs in lepidopterous larvae, 

 and one of them is particularly useful in destroying the cater- 

 pillar of the Cabbage Butterfly [Poiitia Brassiccs). There 

 must occasionally be myriads of these little Ichneumonidae, 

 for we frequently see large clusters of beautiful silky cocoons 

 attached to a single caterpillar, and those whose cases form a 

 sort of honey-comb produce vast quantities. 



Microgaster is nearly related to Bracon and Bassus. The 

 following British species may be thus divided. 



I. Areolet perfect. 



1. M. deprimator Fab. Supp. p. 227. — Panz. 79. II. fern. — Middle of Au- 



gust, Dover. Bred September out of the larvae oi Acronyda Sali- 

 cis. The larvae were only half-grown when 2 maggots came out 

 of two of them, and formed cocoons in August ; in the following 

 May another hatched. 



2. M. globatus Li7m. F. S. n. 1645. — Reaum. t. 2. 2^1- 35./. 2 — 5. — Begin- 



ning of September, Isle of Wight. 



3. M. sessilis Fab. E. S.p. 1 94. 4.—Coq. fab. 4./.8.— Middle of July, Dover. 



4. M. annulipes Curt. Guide. — dorsalis Sjnn.? — Beginning of June, 



Coomb-wood ; beginning of August bred by Mr. C. Fox, from 

 white cocoons out of a Bombyx caterpillar. 



5. M. auriculatus Fab. Piez. 69. 82?— Spin. Ins.Lig. 2. 147? 



II. Areolet imperfect. 



6. M.alvearius Fab.— Curt. B. E.pl. 321.— Reaum. 2. tab. 35./. 7. —The 



only specimens I have ever seen of this beautiful species, were bred 

 from honey-comb cells by my brother. The areolet in some is 

 not so imperfect as in others. 



7. M. glomeratus Li7in. F. S. n. 1646. — Platygaster ovulorum Mag. Nat. 



Hist. V. 3. p. 51.— The beginning of July I bred 20 or 30 from lit- 

 tle yellow cocoons, that 1 found sticking to a caterpillar of Hip- 

 pnrchus papilionarius, but it is generally found upon the larvae of 

 Pontia BrassiccB ; and the reader is referred to Loudon's " Maga- 

 zine of Natural History " for the history and admirable figures of 

 this insect. 



8. M. vitripennis Curt. Guide. — Like the preceding, the nervures stronger, 



and the hinder thighs tipped with brown. 



9. M. lacteipennis Curt. Guide. — Black : wings milky white, stigma and 



costa piceous, anterior tibise and tips of their thighs ferruginous. 

 Middle of August, Dover. 



10. M. tibialis Cz»-f. Guide. — Black: legs ochreous, middle and hinder thighs 



and tarsi piceous : wings subfuscous. 



11. M. lineola Curt. Guide. — Like the preceding, the hinder thighs with a 



piceous line above and below, and the tips of the tibiae piceous. 

 Wings transparent. Out of larvae oi Scava Pyrastri. 



12. M. graciHs Curt. Giiide. — Black: legs pale ochreous, middle and hinder 



thighs, tips of tibiae and tarsi piceous. Bred in September from 

 cocoons found upon grass, by the Hon. C. Harris. 



13. M. atrator Curt. Guide. — Black : tibias and tarsi ochreous, hinder ones 



brownish. 



14. M. Aphidum Lirin. Faun. Suec. p. 410. n. 1643. 



15. M. anomalon Curt. Guide. — Black, body very short and compressed, 



tips of anterior thighs and tibia; ochreous. 

 The plant is Vicia sativa (Common Tare). 



