The Zoologist — January, 1871.. 2437 



savour of the theoretical. It is that, whenever an injurious insect 

 is introduced in our midst, as a general rule the particular parasite 

 or parasites which kept it in check abroad, are not introduced 

 with it." ('Second Report on the Insects of Missouri, 1870,' 

 pp. 12, 13.) 



The preceding extracts are suggestive of a few remarks. Tlie 

 species of Pim])la and of Isosoma were formerly considered to be 

 wholly parasitic and carnivorous. Dr. Giraud observes that Pimpla 

 graminellae and Isosoma are only carnivorous in very early life, that 

 this foundation soon ceases, and that they are herbivorous during 

 the rest of their growth. According to more recent observations, 

 Isosoma is wholly herbivorous. Is Pimpla graminellae also wholly 

 herbivorous, or is I. graminicola its prey in its incipient state? 

 I. graminicola is a synonym of I. hyalipennis, and the latter has 

 not been reared in England with P. graminellae, but with Bracon 

 tenuicornis, which may prey upon it. Are other Ichneumonidoe 

 and Chalcidite partly herbivorous and partly parasitic, like P. gra- 

 rainellce ? and are there times and occasions in which some of the 

 parasitic Hymeuoptera become wholly herbivorous ? Decatoma 

 has been reared from different kinds of oak-galls, and has been 

 supposed to be always parasitic. Is the species of Decatoma 

 above-mentioned parasitic, or is it the cause of the gall from which 

 Pteromalus fulviventris has been reared with it? 



Francis Walker. 



British Oi'uilliology of tlie Year 1870. — At the close of the year, a 

 review of its past Ornithology becomes interesting to the working naturalist : 

 he compares it with other years, and takes stock of the additions it has made 

 to his experience. Few lovers of birds will deny that 1870 has been a year 

 rich in occurrences of rare visitants to our shores ; rich therefore in oppor- 

 tunities of gleaning fresh knowledge of comparatively unknown species. 

 The transitions of temperature during the whole of the year have been 

 abrupt and abnormal; and it cannot be a matter of surprise that they 

 should have had effect upon the migrations of birds. The sudden and 

 severe frost of mid-February sent a number of grebes to the tidal rivers of 

 all parts of the coast. The Sclavonian and rednecked grebes occurred 

 abundantly during the latter part of February and beginning of March along 

 the whole sea-board of the 8.W. peninsula of England. The spring was 

 remarkable for the large arrival it witnessed of the beautiful garganey. The 

 summer will be long remembered by Euglish ornithologists and sportsmen 

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