At this time Linnæus, after having surmounted obstacles which would have crushed a man of ordinary energy, was in the height of his glory; and was professor of botany and natural history in the University of Upsala. His lectures were attended by crowds of students from every country in Europe: he was enthusiastically admired and adored by his students. This influence on the minds of his pupils was almost unbounded; and at Upsala, every student was a natural historian. Bergman had studied botany before he went to college, and he had acquired a taste for entomology from the lectures of Linnæus himself. Both of these pursuits he continued to follow after his return home to West Gothland; and he made a collection of plants and of insects. Grasses and mosses were the plants to which he turned the most of his attention, and of which he collected the greatest number. But he felt a predilection for the study of insects, which was a field much less explored than the study of plants. Among the insects which he collected were several not to be found in the _Fauna Suecica_. Of these he sent specimens to Linnæus at Upsala, who was delighted with the present. All of them were till then unknown as Swedish insects, and several of them were quite new. The following were the insects at this time collected by Bergman, and sent to Upsala, as they were named by Linnæus: _Phalæna._ Bombyx monacha, camelina. Noctua Parthenias, conspicillaris. Perspicillaris, flavicornis, Plebeia. Geometra pennaria. Tortrix Bergmanniana, Lediana. Tinea Harrisella, Pedella, Punctella. _Tenthredo._ Vitellina, ustulata. _Ichneumon._ Jaculator niger. _Tipula._ Tremula. When Bergman's health was re-established, he returned to Upsala with full liberty to prosecute his studies according to his own wishes, and to devote the whole of his time to mathematics, physics, and natural history. His relations, finding it in vain to combat his predilections for these studies, thought it better to allow him to indulge them.