may trick insects into dispersing their seeds. Nonetheless, most mimicry in plants would not be classified as aggressive, as although luring pollinators is similar to cases above, they are certainly not eaten by the plant. However some carnivorous plants may be able to increase their rate of capture through mimicry. For example, some have patterns in the ultraviolet region of the electromagnetic spectrum, much like the spider webs described above. Bipolar mimicry systems Mimicry systems involving only two species are known as bipolar. Only one bipolar arrangement is possible here, namely where the dupe is itself the model. There are two such variants on this arrangement of mimic imitating its target, in the first case, termed Batesian-Wallacian mimicry after Henry Walter Bates and Alfred Russel Wallace, the model is the prey species. In the second case, the model is the host of a brood parasite. Batesian-Wallacian or prey mimicry In some cases of Batesian-Wallacian mimicry, the model is a sexually receptive female, which provides a strong attractive effect on males. Some spiders use chemical rather than visual means to ensnare prey. Female bolas spiders of the genus Mastophora lure male moth-flies (Diptera, true flies, but resembling moths) by producing analogues of the moth species' sex pheromones. Each species of spider appears to specialize in a particular species of prey in the family Psychodidae. Juveniles use their front pair of legs to capture prey, such as flies. Older spiders use a different strategy however, swinging a sticky ball known as a bolas suspended by a silk thread at moths. But both old and juvenile are able to lure prey via this olfactory signal; even young spiderlings have been shown to attract prey species. Beginning in the 1960s, James E. Lloyd's investigation of female fireflies of the genus Photuris revealed they emit the same light signals that females of the genus Photinus use as a mating signal. Further research showed male fireflies from several different genera are attracted to these mimics, and are subsequently captured and eaten. Female signals are based on that received from the male, each female having a repertoire of signals matching the delay and duration of the female of the corresponding species. This mimicry may have evolved from non-mating signals that have become modified for predation. The listroscelidine katydid Chlorobalius leucoviridis of inland Australia is capable of attracting male cicadas of the Tribe Cicadettini by imitating the species-specific