I read with great interest the article “Cervical carotid and Circle of Willis arterial anatomy of Macaque monkeys: A comparative anatomy study” by Kumar et al. (2009). In their description of the aortic arch branching pattern, they noted that the common origin of the brachiocephalic and left common carotid arteries found in Macaque monkeys corresponds to the bovine aortic arch variant found in over one- quarter of humans. The term bovine aortic arch is frequently used to describe the aortic arch branching pattern in which the brachiocephalic and left common carotid arteries have a common origin from the aorta. However, the origin of this term is unknown. As previously noted (Layton et al., 2006; Buerkel and Gurm, 2007), this branching pattern is a misnomer as it is not present in cattle. It has been suggested that the name bovine arch was applied due to the similar appearance that this branching pattern has to a cow's horns (Vitek, 2007). This assertion has been disputed (Layton et al., 2007), and the true origin of the name remains unclear. Since this branching pattern is the normal aortic arch branching pattern found in a number of animals, some have suggested changing the name of this variant to one that correctly reflects the anatomy of the aortic arch branching pattern found in the species. Proposed names include the feline, canine, or lapine arch (Elster, 2008). However, given the relative biological similarities between humans and monkeys, and consequently the frequent use of monkey models when studying human physiology and pathophysiology, it might be more fitting to replace the term bovine arch with simian arch. Netanel S. Berko*, * Department of Radiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York.