A pragmatic intertext (PI) involves the activation and interaction of two texts, with the later 'alluding text' (e.g., 'Home Smart Home') quoting or reflecting the earlier 'source text' (e.g., 'Home, Sweet Home') in such a way that the recipient can perceive or infer the intertextual reference. This article analyzes PIs drawn from 1,500 New York Times (NYT) and 1,500 United Daily News (UDN) news headlines to shed light on their occurrence frequencies, source texts, common grounds, and sociocultural implications. It is found that the PI occurrence frequencies are quite close, but the PI density of the NYT headlines is higher than that of the UDN ones. The source text represents the intertextual common ground and reflects the cultural modality of the intertextual association. The NYT headlines contain much more PIs derived from the cultural modalities of formulaic expressions, non-print media products, literary works, and non-literary works. On the other hand, the UDN headlines demonstrate much more extensive use of deviated general expressions. This contrast gives an overview of the paradigmatic linguistic and cultural knowledge underlying the writing and reading of the PIs in the two groups of headlines. In addition, as many as half of the UDN PIs are punning or metaphorical ones with a general expression as their source text, much more than their counterparts in the NYT headlines. PIs of this type are easier to evoke, albeit with less de-familiarized ingenuity. Most UDN punning PIs are homonymic, while most NYT punning PIs are both homonymic and polysemic.
