Words such as "glasses" and "species" are in their plural form according to English pluralization rules. Regarding the lemmas, with some exceptions:

1. EWT uses the plural form as the lemma, matching its intended use;
2. GUM uses the singular form as the lemma, presumably using the machine-lemmatized plural form.

EWT is correct here, but these cases are very likely to confuse lemmatizers trained on the UD English corpora due to these cases not following the English plural lemmatization rules.

Making use of the plurale tantum annotation (Number=Ptan) which already exists would make the intention clearer, and allow lemmatizers to differentiate from NNS/Number=Plur and NNS/Number=Ptan.

Note: This should also apply to the dates like 1980s where the lemma retains the form's plural suffix.

Relevant issues:

1. EWT -- Ambiguous lemmatization of pluralia tantum UD_English-EWT#374
2. PUD -- Plural nouns not using singular lemma, possible pluralia tantum UD_English-PUD#33