INTRODUCTION ccxix 



the pith cavities of certain forest trees. Prognathogryllus stridulans, once a difficult 

 insect to obtain in the mountains round Honoluki, has now become common, owing to 

 the unhealthy state of many of the arborescent lobelias in this locality, as elsewhere in 

 the islands. At the present time and in fact for the last ten years many of these trees 

 have lost their former healthy condition, and are now either entirely dead or have many 

 dead branches. These dead branches being hollow afford a most convenient home for 

 Prognathogryllus, and rarely is a tree found in this condition which does not harbour 

 the cricket in some or all stages. In former years it was most difficult to find a tree in 

 the dead and dry condition suited for these crickets, and they were then more often 

 obtained by splitting dead twigs and branches of Piptiirus, an urticaceous tree. The 

 males of Prognathogryllus stridulate only at night, after they have emerged from their 

 retreats. The species of Leptogryllus have rather varied habits which, however, are 

 not altogether constant in the case of a single species. Several (Z. elongatus, kajiaiensts 

 e.g.) have been found numerously, hiding in dead hanging fronds of tree-ferns, or 

 [L. fusconotatiis, elongatus, nigrolineatus) amongst dead masses of banana leaves still 

 adherent to the plant, beneath bark of trees (Z. siinillimus), or under moss or creeping 

 ferns [L. forjicularis). Another favourite hiding place for several species is at the base 

 of the leaves of Freycinetia, where we have found Z. nigrolineatus, L. similis, L. fus- 

 conotatus and other species. These crickets are sought after both by some of the 

 Drepanid birds and also by the Meliphagine ' Oo ' of Kauai. Adults and nymphal 

 forms are usually found in company. Some of the Leptogrylli feign death, lying with 

 the body somewhat crescentically curved. No parasites of those crickets are yet 

 known, but it is quite likely that the eggs may be attacked. 



In concluding this brief account of the Orthoptera a few words may be said on the 

 endemicity in the islands of the species of the more important genera and families. In 

 the genus Paratrigonidium the species are so difficult and have been so little collected 

 in many places that not much confidence can be placed on the correctness of their 

 distribution, as at present known. Yet, no doubt, while some are more widely dis- 

 tributed, others are peculiar to a single island. Thus clearly P. saltator of Oahu 

 represents the P. freycinetiae of Hawaii, the two being very closely allied and having 

 identical habits. Probably P. subroseum, P. roseum, and P. atroferrugineum, inhabiting 

 Oahu, Maui and Molokai, are modified forms of one original species, for they have 

 peculiar and similar habits. Different in appearance as these are in the adult stage, 

 yet the nymphal stages of all are alike and the nymphs are quite unlike the mature 

 crickets. 



The endemicity of the species Banza {^Brachynietopd) is no doubt great, and no 

 one species has been found on more than one island, though it is possible that B. molo- 

 kaiensis and B. matiiensis of Molokai and Maui are really one species. 



In the Prognathogryllidae, Prognathogryllus has not yet been found on Hawaii, 

 though it occurs on Maui, while Thaumatogryllus is only known from Kauai. The 



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