The ubiquitous symbol of the elephant may or may not have been associated with Buddhism. On some coin series of Antialcidas, the elephant holds the same relationship to Zeus and Nike as the Buddhist wheel on the coin of Menander II, tending to suggest a common meaning for both symbols. Some of the earlier coins of king Apollodotus I directly associate the elephant with Buddhist symbolism, such as the stupa hill surmounted by a star, also seen, for example on the coins of the Mauryan Empire or those of the later Kuninda kingdom. Conversely, the bull is probably associated with Shiva, and often described in an erectile state as on the coins of Apollodotus I. Also, after the reign of Menander I, several Indo-Greek rulers, such as Agathokleia, Amyntas, Nicias, Peukolaos, Hermaeus, Hippostratos, Menander II and Philoxenus depicted themselves or their Greek deities forming with the right hand a benediction gesture identical to the Buddhist vitarka mudra (thumb and index joined together, with other fingers extended), which in Buddhism signifies the transmission of the Buddha's teaching. At precisely the same time, right after the death of Menander, several Indo-Greek rulers also started to adopt on their coins the Pali title of "Dharmikasa", meaning "follower of the Dharma" (the title of the great Indian Buddhist king Ashoka was "Dharmaraja" "King of the Dharma"). This usage was adopted by Strato I, Zoilos I, Heliokles II, Theophilos, Peukolaos, Menander II and Archebios. Altogether, the conversion of Menander I to Buddhism suggested by the Milinda Panha seems to have triggered the use of Buddhist symbolism in one form or another on the coinage of close to half of the kings who succeeded him. Especially, all the kings after Menander who are recorded to have ruled in Gandhara (apart from the little-known Demetrius III) display Buddhist symbolism in one form or another. On the contrary, none of the kings whose rule was limited to Punjab did display Buddhist signs, with the exception of the powerful Hippostratos, who probably took under his protection many Gandharan Greeks fleeing from the Indo-Scythians. A 2nd century BCE relief from a Buddhist stupa in Bharhut, in eastern Madhya Pradesh (today at the Indian Museum in Calcutta), represents a foreign soldier with the curly hair of a Greek and the royal headband with flowing ends of a Greek king.