 Slow lorises range in weight from the Bornean slow loris at 265 grams ( 9 @.@ 3 oz ) to as much as 2 @,@ 100 grams ( 74 oz ) for the Bengal slow loris . Slow lorises have stout bodies , and their tails are only stubs and hidden beneath the dense fur . Their combined head and body lengths vary by species , but range from 18 to 38 cm ( 7 @.@ 1 to 15 @.@ 0 in ) between all species . The trunk is longer than in other living strepsirrhines because they have 15 – 16 thoracic vertebrae , compared to 12 – 14 in other living strepsirrhines . This gives them greater mobility when twisting and extending towards nearby branches . Their other vertebrae include seven cervical vertebrae , six or seven lumbar vertebrae , six or seven sacral vertebrae , and seven to eleven caudal vertebrae . 
