380 Rev. T. A. Marshall on new Genera 



Australian Hydroid, of which, however, he possessed specimens of 

 only the dried periderm. It would seem to oifer one of the connect- 

 ing forms by which the Campanularian pass into the Sertularian 

 Hydroids through Coppinia, Reticularia, and Grammaria ; but, in 

 the absence of all knowledge of the living animal, it is impossible to 

 speak with decision as to its affinities. 



Lineolaria spinulosa, Hincks. 



XXXVI. — Descriptions of new Genera and Species of Eumolpida 

 from the Collection of the Rev. Hamlet Clark. By the Rev. 

 T. A. Marshall. 



The time has not yet arrived when a satisfactory arrangement 

 of this interesting yet difficult group can be hoped for by ento- 

 mologists. The literature of the subject is in so confused and 

 imperfect a state, and the undescribed forms are so numerous, 

 that the materials for generalization are yet wanting, and much 

 time must elapse before a sufficient groundwork for the system- 

 atist can be established. The existing materials require to be 

 thoroughly sifted, and several hundreds of undescribed species 

 to be defined, before the work of organization can begin. To 

 the former of these tasks, with a view to attempting the two 

 latter, the present writer has been led to direct his attention j 

 he is therefore enabled to speak with some certainty of the na- 

 ture of the difficulties to be encountered. With respect to the 

 hitherto published genera and species, it is perhaps not too much 

 to say that one-half are insufficiently characterized, and rather 

 impede than facilitate future labours. The writers in whose 

 widely scattered works these descriptions are to be found vary 

 much, as may be supposed, in their style and accuracy : a few 

 only have performed their task in a perspicuous and permanent 

 manner. Foremost among these is Mr. Baly, whose labours in 

 this department are beyond all praise for minute accuracy and 

 clearness. The descriptions of Prof. Boheman, of Blanchard, 

 Germar, Thomson, Say, Lucas, Gerstacker, Leconte, and a few 

 others are easy of verification. It is to be regretted that most 

 of the other authors whose names are attached to described 

 species have contented themselves for the most part with a brief 

 and insufficient diagnosis, and often a mere indication. A few 

 only of the genera can be regarded as permanently established : 

 even the well-known Colaspis, as at present defined, will not 

 exclude a number of forms obviously distinct. The uncharac- 

 terized genera of Dejean^s Catalogue embrace for the most part 

 apparently natural groups, or at least they may be made to do 

 so by a system of judicious exclusion. We will therefore first 

 direct our attention to them, from a conviction that the conver- 



