broadsheet for his match against the bitch states he was open to challenges from "any dog in England for 100 Guineas of 24lbs being double his own weight". According to Lennox: Lennox writes that after several fights, Jacco adapted his technique and would overcome his canine opponents by leaping directly on their backs and manoeuvring himself into a position where he could tear at their windpipes while remaining out of reach of their jaws. Lennox reports him as having overcome fourteen opponents in total and the advertising broadsheet states he had already been involved in thirteen matches "with some of the best dogs of the day including his combat with the wonderful bitch Puss of T. Cribbs and the famed Oxford one". Both Berkeley and Lawrence Fitz-Barnard (writing in Fighting Sports in 1922) cast doubt on Jacco's ability to beat any canine opponent in an un-rigged match though. Berkeley points to the bleeding of the dogs by Cribb and stresses the tendency of writers to exaggerate their accounts of simian ferocity and strength, while Fitz-Barnard dismisses out-of-hand the possibility of any but the largest apes being able to prevail against a fighting dog. Fitz-Barnard claims that Jacco was a "stock performer and put up a great battle with an indifferent dog. The monkey was given a club to assist him..." Most accounts agree that Jacco was held in a small cage when not fighting and was secured by a short length of thin metal chain during his matches. Identification Which species of monkey or ape Jacco belonged to is unknown. Lennox initially describes him as coming from Africa, but later writes that he belonged to the Asian gibbon family: Egan describes him as the "famed Italian monkey", Umberto Cuomo writing in Il Bulldog in 2002 says he was probably a mandrill. Before Aistrop had acquired Jacco, he had featured a baboon at the Westminster Pit in an attempt to capitalise on Jacco's growing fame, but, according to Lennox, this had only served to emphasise Jacco's skill by comparison. Neither the Cruikshanks' aquatint nor Henry Aitken's depiction of Jacco fighting an unidentified opponent are detailed enough to identify Jacco's species, even if they are taken from life (the Cruickshanks are more interested in depicting the spectators than in the accuracy of the depiction of the monkey). Landseer's etching shows Jacco with a short tail and is annotated with "...from a sketch