After him the elder +Pliny+ gave a sanction to the opinions which he found prevalent, and added to them others of his own. But Pliny, though a laborious compiler, occupied himself with too great a variety of pursuits to attain excellence in any. As a naturalist, however, he is happy in some of his descriptions. To him we are indebted for the transmission to us of all that was actually known, or supposed to be known, of natural history in his day. I say--supposed to be known, for many of the opinions and conjectures which he has put forth, have been shown by modern investigators to be ill-founded. The notions of the ancients respecting natural philosophy rested on no rational foundation; ideas of charms and of planetary influence directed their most important pursuits, and led to the formation of very absurd theories. When the writer last named recommends that the dust in which a mule has rolled should be sprinkled on persons who are violently in love, as a sovereign remedy for amatory ardour, and gravely tells us that snakes are sometimes produced from the human medulla,--with much nonsensical stuff of the like kind; we may safely pronounce that he or his contemporaries or both were very credulous, and that the science of experimental philosophy was scarcely cultivated among them. After the compilation of Pliny's vast Compendium, nearly fourteen hundred years rolled away without anything being done for entomology or for natural history in general. +The Arabians+, who alone preserved a glimmer of science during those dark ages that succeeded the fall of the Roman empire, cultivated natural history only as a branch of medicine, and from their writings little can be gleaned in furtherance of our present object.