THE BRITISH NATURALIST. 



[June 



fine specimen of Campontia was dredged up adhering to sea weed from a 

 depth of over 10 fathoms. 



I have recently learned that Dr. Packard, of America, has recorded 

 the discovery of a marine Dipterous larva in 15 fathoms off Salem 

 Harbour, which he has named Chironomus oceaniciis.* I have carefully 

 compared my specimens with his drawings, and it is quite certain they 

 are not the same species, the mandibles being slightly different, but more 

 particularly the retractile hooked appendages on both the fore and hind 

 legs vary considerably, and the respiratory tubules possessed by 

 Campontia are not visible on the American species. 



FIG 2. CHIRONOMUS DORSALIS IMAGO. 



The great difficulty I experienced in finding any one in England to 

 assist in naming this and other species of Dipterous larvae I have met 

 with, prompted me to write these notes ; I have applied to many of 

 the principal authorities on Diptera, only to find that there are several 

 families, in which the life histories of only a very few species have been 

 worked out. Surely, there are many excellent members of our Micro- 

 scopical Societies throughout England, who only need the fact bringing 

 home to them to induce them to make some attempt, however feeble, 

 to fill up this gap, especially as the subject is a very interesting one, 

 and the material abundant. The difficulty of obtaining specialists to 

 undertake the work of describing many groups of insects has been 

 recently referred to by the Editor of Natural Science, for he states 

 that though Mr. Whymper's " Travels amongst the Great Andes 

 of the Equator," were completed over 12 years ago, the 

 volume in which the Zoological collection was described has been 

 only recently issued, and this with several large groups of 

 insects omitted, as no one has been found able to describe them. 

 Professor Miall, to whom I sent my specimens, suggested that Johnston's 

 Campontia was most probably Schiner's Thalassotnyia Fraiienfeldi. 

 Schiner, however, gives no drawing nor any account of the larva in his 

 " Fauna Austriaca," page 596, Vol. II. I feel sure, however, from the 



* See Transactions of Essex Institute, V ol. 6, page 42. 



