Fiddler ray snouts are translucent. The fiddler rays are also distinguished from other guitarfishes in that the anterior nasal flaps of their nostrils are expanded backwards and fused together into a nasal curtain that reaches the mouth. Fiddler rays feed on bottoms shellfish, crabs, and worms, which they crush between their jaws. The eastern fiddler ray is known to scavenge from fish traps. Like other guitarfishes, fiddler rays are ovoviviparous. The egg capsules of the southern fiddler ray are reported to be golden in colour, containing three embryos each. It gives birth to litters of four to six young per breeding cycle.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection paper, consisting of the letter and papers, was published in the "Zoological Journal of the Linnean Society 3" (20 August): 46–50. The paper consisted of a communication letter by Joseph Dalton Hooker and Charles Lyell dated 30 June 1859, giving information on the three sections of the papers. The introduction is shown below, along with the section headings: MY DEAR SIR,—The accompanying papers, which we have the honour of communicating to the Linnean Society, and which all related to the same subject, viz. the Laws which affect the Production of Varieties, Races, and Species, contain the results of the investigations