Horace Serm. 1.10. 61), when censuring careless and rapid compositions, illustrates his observations, by referring to a Cassius Etruscus, whom he compares to a river in flood rolling down a turbid torrent, and adds, that the story ran that this poet, his works, and book-boxes, were all consigned together to the flames. Here Acro, Porphyrio, and the Scholiast of Cruquius agree in expressly declaring that the person spoken of is Cassius Parmensis, and the latter makes mention of a tragedy by him, called Thyestes, as still extant.

Again, Horace (Hor. Ep. 1.4. 3), when writing to Albius, who is generally believed to be Tibullus, questions him with regard to his occupations, and asks whether he is writing anything " quod Cassii Parmensis opuscula vincat." Here the old commentators quoted above again agree in asserting that this Cassius served as tribune of the soldiers in the army of Brutus and Cassius, that he returned to Athens after their defeat, that L. Varus was despatched by Augustus to put him to death, and, after executing the order, carried off his port-folio; whence a report became current, that the Thyestes published by Varus was really the work of Cassius stolen and appropriated by his executioner. To this narrative Acro and the Scholiast of Cruquius add, that he composed in various styles, and that his elegies and epigrams were especially admired.

These two passages and the annotations upon them have been the foundation of a lengthened controversy, in which almost all writers upon Roman literature have taken part. A variety of opinions have been expressed and hypotheses propounded, many of them supported with great learning and skill. A full account of these will be found in the essay of Weichert "De Lucii Varii et Cassii Parmensis Vita et Carminibus," (Grimae, 1836,) who, after patient examination, has shewn by many arguments, that the following conclusions are the most probable which the amount and nature of the evidence at our disposal will enable us to form:

1. Cassius Etruscus and Cassius Parmensis were two separate personages. It is the intention of Horace to hold up the first to ridicule, while his words imply a compliment to the second.

2. Cassius Parmensis was one of the conspirators who plotted the death of Caesar. He took an active part in the war against the triumvirs, and, after the defeat and death of Brutus and Cassius, carried over the fleet which he commanded to Sicily, and joined Sextus Pompeius, with whom he seems to have remained up to the period of the great and decisive sea-fight between Mylae and Naulochus. He then surrendered himself to Antonius, whose fortunes he followed until after the battle of Actium, when he returned to Athens, and was there put to death by the command of Octavianus. These facts are fully established by the testimony of Appian (App. BC 5.2) and of Valerius Maximus (i. 7.7), who tells the tale of the vision by which Cassius was forewarned of his approaching fate, and of Velleius (2.88), who distinctly states, that as Trebonius was the first, so Cassius Parmensis was the last, of the murderers of Caesar who perished by a violent end. The death of Cassius probably took place about B. C. 30; and this fact alone is sufficient to prove that Cassius Parmensis and Cassius Etruscus were different persons; the former had held a high command in the struggle in which Horace had been himself engaged, and had perished but a few years before the publication of the epistles; the former is spoken of as one who had been long dead, and almost if not altogether forgotten.

3. We have seen that two of the Scholiasts on Horace represent that Cassius composed in different styles. We have reason to believe that he wrote tragedies, that the names of two of his pieces were Thyestes and Brutus, and that a line of the latter has been preserved by Varro (L. L. 6.7,ed. Mülller). In like manner, a single line of one of his epigrams is quoted by Quintilian (5.2.24), and a single sentence from an abusive letter addressed to Octavianus is to be found in Suetonius (Suet. Aug. 4); in addition to which we hear from Pliny of an epistle to Antonius. (Plin. Nat. 31.8.) Many persons, and among these Drumann, believe that the letter to be found in Cicero (Cic. Fam. 12.13) is from the pen of Cassius Parmensis, and strong arguments may be adduced in support of this opinion; but, on the whole, we are led to conclude from its tone, that it proceeded from some person younger and holding a less distinguished position than Cassius Parmensis at that time occupied.