386 Transactions. — Miscellaneous. 



ing with specimens of Hydriomena deltoidata. These moths 

 were so abundant that four or five specimens would fly out of 

 a single bush, and frequently two or three specimens would be 

 captured in the net at once. In fact, the abundance of this 

 particular species was most embarrassing to the collector, as 

 it was liable to be mistaken for many rarer, though somewhat 

 similar, species. Last summer (1899-1900) I certainly did 

 not see more than a dozen specimens of H. deltoidata, and 

 it cannot now be called a really abundant species. I have 

 noticed the insect steadily declining in numbers during the 

 whole of my entomological experience in the neighbourhood 

 of Wellington, and I am inclined to attribute it partly to the 

 increase in the number of sparrows, and partly to the denuda- 

 tion of the forests, for, although I have only found the larva 

 of this insect feeding on a species of Plantago, I am inclined 

 to think that it also probably feeds on some of our native 

 ferns. The moth used to be most abundant amongst luxurious 

 patches of ferns in rather open spots in the forest, and it is 

 still common in such localities, when these are situated far 

 away from settlement. 



Another species that has declined equally in numbers 

 during the same period is Somatochlora smithii. During 

 the past three years I have been specially anxious to obtain 

 many examples of this, and, in fact, of all our native dragon- 

 flies, and its comparative rarity has consequently been some- 

 what forcibly brought under my notice. In 1883, 1 remember, 

 this insect was abundant over every stream in Karori, and at 

 that time I used to frequently observe the females depositing 

 their eggs in the water, the long abdomen being beaten vio- 

 lently on the surface during the process. Now, however, it 

 would be quite impossible to make any such observation. In 

 fact, during the whole of the past summer I saw only two 

 specimens at Karori, and these seemed to have come from a 

 distance, as they were flying very high in the air, apparently 

 migrating. The larva of this insect lives in the mud at the 

 bottom of stagnant streams and ponds, and may, perhaps, 

 have been destroyed by the ever-increasing number of trout, 

 otherwise it is difficult to understand what causes can have 

 led to the great decrease which has taken place in the num- 

 bers of the perfect dragon-fly. Introduced insectivorous birds, 

 through feeding on the imago, may, again, be suggested as 

 a cause of decadence ; yet the insect is an extremely rapid 

 flier, and should be able to avoid capture to a great extent. 

 However, the fact of a great decrease in the number of speci- 

 mens of S. smithii in this district is certain, whatever may be 

 the cause to which we may attribute it. 



A great number of the forest-dwelling species in New 

 Zealand are nocturnal in their habits. These can only be 



