Mr. Hassall on the Phosphorescence of Zoophytes. 341 



sary a careful investigation of the structure of the maxillae in 

 both sexes of the types of the different subgenera and genera 

 of Cetoniida, in order to learn their natural relations. Beyond 

 this, however, there are various other particulars which are 

 requisite to be determined before we can introduce a single 

 species of Melitophila into its natural position with respect to 

 the others. It will be serviceable to give these in the words 

 of Burmeister's letter : — " In the first place, it is necessary to 

 determine whether the specimen under description be a male 

 or female ; the former sex may be known by the channelled 

 ventral surface of the abdomen, the convex perpendicular py- 

 gidium, and the anterior tibiae, which are often narrower and 

 toothless, whilst the female has two or three teeth on the out- 

 side. The maxilla must then be examined to determine 

 whether the galea or upper lobe be corneous, arcuated, trigo- 

 nate, with simple or cleft apex ; or membranous, arcuated, or 

 truncated at the apex, and of smaller size. In like manner 

 the lower lobe or mando must be examined to determine whe- 

 ther it be armed with a tooth or unarmed, according to the 

 sex : — the form of the clypeus, the mesosternum, prosternum 

 (whether it possess a spine in front of the coxae or not) ; the 

 tarsi (whether longer or shorter than the tibiae) ; the tibiae, de- 

 termining the number and position of the teeth according to 

 the sex ; the emargination of the elytra above the coxae, whe- 

 ther very deep as in Schizorrhina, or very feeble as in Golia- 

 thus. The form of the under lip is also very important in the 

 Cremastocheilida." Besides these characters, the form of the 

 mandibles, the outline of the prothorax, and the existence of 

 onychiae between the ungues of the tarsi ; and lastly, the va- 

 riation in the form of the antennae, according to the sexes, 

 must be noticed. 



Unless such particulars as these are attended to, we may as 

 well content ourselves with the Linnaean or Fabrician state of 

 the science, instead of doing our utmost to give to it a higher 

 and more philosophic tone. 



XLIV. — On the Phosphorescence of Zoophytes. By Arthur 

 Hill Hassall, Esq. M.R.C.S.L., Corresponding Member 

 of the Dublin Natural History Society. 



To the Editors of the Annals of Natural History. 



Gentlemen, 

 On reading the Rev. D. Landsborough's paper on the Phos- 

 phorescence of Zoophytes in your last Number, p. 281, I am 

 led to refer to my paper read before the Natural History 

 Society of Dublin, November 6, 1840, and published in your 



