[110] Mr. Verrall assures me that even in the present day it is quite impossible to recognise the species of Diptera described by persons unacquainted with the particular group, and that Browne's remarks would apply to hundreds of species. It is possible that an _Ephydra_ may be meant. This genus of small flies, says Mr. Verrall, abounds in such places as Browne describes, but it is likely that other species were with them. worthy Sr I shall be euer redie to serue you who am Sr your humble Seruant THO BROWNE. _Norwich, Sep 16. 1668._ No. IV. "_The fourth Letter to Dr. Merrett Decemb xxix._" [1668] [_Fol. 42 verso._] Sr I am very joyfull that you haue recouered your health whereof I heartily wish the continuation for your own and the publick good. And I humbly thank you for the courteous present of your booke.[111] with much delight and satisfaction I had read the same not once in English I must needs acknowledge your co[=m]ent more acceptable to me then the text which I am sure is an hard obscure peice without it. though I haue not been a stranger unto the vitriarie Art both in England and abroad. [111] This evidently refers to the gift of a copy of Merrett's Latin translation of Antonio Neri's _L'Arte Vetraria_ (Firenze, 1612, 4to), published under the title of "The Art of Glass, translated into English with some observations on the Author," &c., in 1662, and a Latin edition in 1668. I perceiue you haue proceeded farre in your Pinax. These few at present I am bold to propose & hint unto you intending God willing to salute you agayne. A paragraph might probably be annexed unto Quercus. Though wee haue not all the exotick oakes, nor their excretions yet these and probably more supercrescences productions or excretions may bee obserued in England. Viscum--polypodium--Juli pilulæ-- Gemmæ foraminatæ [formicatæ?] folior[=u]-- excrement[=u] fungosum verticibus scatens-- Excrementum Lanatum-- Capitula squamosa jacææ æmula. Nodi--melleus Liquor--Tubera radicum vermibus scatentia--Muscus--Lichen-- Fungus--varæ quercinæ.[112] [112] The Rev. E. N. Bloomfield has most kindly assisted me in attempting to identify the Parasitic products of the Oak mentioned above: _Viscum_, is doubtless the Mistletoe. _Polypodium_, the Common Polypody Fern. _Juli pilulæ_: "little balls on the flower catkins." The Currant Gall, _Neurosterus baccarum_, which is the spring form of _N. lenticularis_; Oliv. _Gemmæ foraminatæ [formicatæ?] foliorum_: "pimple-like buds on the leaves." Leaf-galls, such as the Silky Button, _N. numismatis_, Oliv., and the common Spangle, _N. lenticularus_, Oliv. _Excrementum fungosum verticibus scatens_: "a spongy secretion bursting out from the ends of the shoots." The Oak Apple, _Biorhiza terminalis_, Fab. _Excrementum lanatum_: the Woolly Gall, _Andricus ramuli_, L., a somewhat rare Gall, resembling a ball of cotton-wool.